Quicksand Fans

I came across a mud pit while I was roaming a stream today, and at first it was just a puddle of water on top of mud, but after playing with it for a while, it turned out there was about 2.5-3.5 ft of mud under this whole puddle, which was like 8ft long by 3 ft wide. Well since it was so shallow, I am wondering how can I sink to make it look like I'm sitting really deep, like shoulder depth? I was able to hit waist, but I want to try looking like I am sitting deeper.

Thank you.
Maps

I would say to sit down like submerge your lower body like slouching then you'd keep your torso in a vertical position just to simulate being in deep mud.

First, if there isn't too much water on top, you can loosen the mud by mixing the water down into it, pulling up blobs and squeezing/rubbing it between your hands in the water, using your feet to bring up the stuff from deeper down. Then, that way, you may either be able to eliminate the water on top, or reduce the amount of water, but expand the depth of the mud, and perhaps get it worked/loosened deeper as well for easier, deeper sinking.

As for getting down deep in shallow mud, what you can do when the mud isn't deep enough, is to work your feet/legs forward along the bottom, out from under you, gradually getting into more and more of a sitting position until you are as deep as you want, such as shoulder deep, chin deep, face deep, or submerging. If you aren't deep enough when you are sitting right on the bottom, you can then lean back, pushing mud from beside/behind you to in front of your chest, to let the mud swallow you deeper.