One of the tough things about sci-fi and fantasy as a genre is that this completely made-up world is all your head, and the reader has no clue what picture you’ve painted. To get the reader primed to visualise the story, you need to walk the reader through the experience. Your depiction of this Mars colony barely goes over two lines:
It was the year 3521. Mars had finished being terraformed just 8 Earth years ago. Tessa was on a tourist trip from the Titan colony to Mars, and with futuristic technology, it only took her a few hours in her personal travel pod. She landed at Transition City, where the Northern Ice Cap Basin Sea met the continent of Lequitua.
She’s going where next to what on where? What are these places? What’s a travel pod? What’s futuristic technology? (also out of place, because in the story’s setting, it wouldn’t be futuristic). You’ve got to establish these elements before you proceed so the reader is on the same page as you.
Most importantly, follow the rule “show, don’t tell”. Put us in the character’s shoes and gives as an experience that uses our senses. For example:
“Tessa looked out from the window of her pod. The formerly barren landscape of Mars, as the holo-documentaries showed, was a lush, terraformed world. Where there were dried canyons were now rich water systems. It was hard to believe that there could be marshes and wetlands, particularly around the industrious Transition City. Even with cheap low-atmosphere vehicles, access to Transition City was only possible via the old-fashioned method of terrestrial travel, though the hovercar technology made the ride comfortable.”
It’s not hard for the reader to get a “feel” for being in this future world with that kind of storytelling, because it’s a common experience – no different to looking out the window of your car during a road trip.
As for developing your sci-fi world, take a look at a piece I wrote five years ago, “Maiden Flight” (viewtopic.php?f=14&t=1555):
There were a lot of things Marie had to learn about surviving in the colonies. The utopia of Earth was a long way away – almost mythical. She recalled stories of a time when the people of Earth dreamt of space travel and encountering distant civilisations. Centuries later, the only civilisations they encountered were the numerous space colonies established by humans throughout the galaxy. There was still an infinite amount of space to explore, but so far no intelligent life forms. Of course, as a military freight pilot, Marie didn’t need to know about the science of life in the outer realms of space, and she found herself standing in front of the division headquarters. A legacy of humanity’s military might, the headquarters stood out, being constructed of various metals to form tall monuments to the struggles of humankind on Earth and in space. In the spacious fields around the headquarters, troops still practiced the drills of old, though the old-fashioned ballistic weaponry twirled around by the drill platoons were merely relics of the distant past.
The interior seemed more spacious. While some groups protested that the headquarters took up far more space than was necessary – and living space being a premium in the colonies – there was no mistaking that this was the centre of the strength of mankind. Turbolifts took visitors to any office for any purpose, and the foyer was a long marble hall with portraits of Earth’s leaders. Flags hung along each side of the hall. Where they were once national flags of countries of old, there were now emblems of the many republics and colonies that have sprung up in the past century. The headquarters felt more like a capitol building than a military structure, but that was simply the importance the military had on galactic affairs.
Marie exited the turbolift and entered the quartermaster’s office. The door slid open to reveal a mahogany desk and the quartermaster – a middle-aged officer in a traditional green uniform. Marie stood at attention and saluted.
‘Lieutenant Renoa, reporting for duty, sir,’ she said.
‘At ease, Lieutenant,’ said the quartermaster. The name tag on his desk revealed his name to be Colonel Robert G. McMahon – a name with ancient Earth roots that distinguished Earth-born families from the outlanders, like Marie. Colonel McMahon typed a few commands on his computer and brought up Marie’s profile.
In writing this, I put the reader through Marie’s eyes, showing the world I created in a way that Marie would have experienced it, and in doing so making connections between this world and the one we live in. It’s not necessary to create a Star Wars level of expanded universe, but this setup clearly establishes the time and technology, and gives some context to the events of the story.
Using original settings is one of your strong points, and you should take the time – and enjoy – building your imaginary worlds.
On “artificial” storytelling
I use “artificial” to describe a story that has elements that are forced into the story just to make something happen – call it convoluted, unnecessary and even hammy. Basically, it feels like you’re trying too hard to get Tessa into the quicksand as soon as possible, and the descriptions and dialogue are what many would call “lame”.
The epitome of this would be something like: “Sandy lived in Quicksand City on Quicksand Planet. It was really dangerous because it had quicksand. So she became a Quicksand Ranger.”
So you’ve set up Transition City that “surrounded by mudflats, bogs, swamps, and marshes on land, making it nearly impossible to leave on foot.” Plausible enough so far, but it’s increasingly obvious that your character is going to encounter quicksand within the next two paragraphs.
What caps this problem off is that there is a “Transition City Quicksand Rescue” team. What? Why? How? Why is this so specifically named, as compared to…I dunno, Mars Rangers? Does Transition City have other special teams like the Transition City Wader Replacers? Transition City Portable Toilet Team? Transition City Bras-on-Demand? Do other cities also have Quicksand Rescue departments? That’s a literary can of worms you’ve opened up there.
Try to keep your plot elements “natural”. Let the scenes happen as part of reasonably plausible plot development instead of ramming your characters into peril and making them scream “Oh no I’m about to crash into quicksand and I don’t have the right shoes on”.
On being a large ham
Part of creating a convincing character is to present them in a way that allows the reader to get into their heads. In this case, Tessa’s dialogue is oddly specific in an illogical way. Tessa calls out lines like:
"My clothes have special cleaner threads because they were made in this city! I wish they had come with a thing to get me out of this situation, though!"
What? She’s stepped into a marsh and she’s actually verbalising this? What the heck does it even mean?
Then later she says:
"Please help! You look like you're dressed for mud!"
She’s in a deadly situation and the first thing she identifies is her potential rescuer wearing mud-appropriate clothing? Que?
Even this line:
Looking through the clothes, Tessa noticed something.
"Don't you have a bra?" she asked
"Eh, if you just survived quicksand, you can be daring enough to not need a bra," said Jekobi dismissively.
I like having at least one of my characters braless. But, think about the context and what you’re doing with this. Is there a reason why you’ve spent three lines haggling over a bra? Is there going to be a point in the story where not having a bra is going to make a difference? Why is this conversation even happening? Is Jekobi going to be distracted by Tessa’s braless boobs that she crashes into another quicksand bog? If not, this sort of thing doesn’t need to be said. Hint at it at most, but this kind of fixation on minor details pulls the story in random directions.
The epitome of hammy storytelling is basically when Tessa wishes there was a hose, and Jekobi happens to turn the road into a giant pool of water. What the heck? Why is this even a thing?
I’d like to see you make more of an attempt to build the story in a way that makes sense, rather than take shortcuts to “explain” things in implausible ways (and I've said this before with your story suddenly featuring mutant superpowers). Don’t sink to the level of “Oh gee, I wish I had a Quicksand Escaper 5000!” “Oh! I have one in my pocket!”.