It takes a few of these to warm up! You have the right idea here, I think you can try a few different techniques that could help you feel better about the rhythms. One thing you could try is lightly sketching in an "envelope" to give yourself an idea of how the overall pose is proportioned. You could also use the measuring techniques from the How to Draw Accurate Proportions video to sketch in some guidelines to achieve the same result. After that, finding the angle of the shoulders and pelvis gives you a bit of structure to work off of and you can really explore and let loose with your rhythms. Try to find the largest rhythms first, especially the ones that flow from the torso to the legs. As you get the basic rhythms in, you can go back and refine -- so make sure you keep your lines light at first. Just some suggestions. You're on the right track here. I would say the most important thing is to try to lighten up on the pressure a bit and try to make more committed lines.

Great flow! Try incorporating more areas of straight lines to counterbalance the curves, as that can bring a more dynamic change into the curving rhythm. Also, look for areas of overlap in the seal's outline, such as whenever the neck would be in front of the body or the seal twists in a way that creates folds. Emphasizing the overlap can really make the shape take more definition and dimensionality. Hope this helps, keep up the good work! :)

Youre doing great! I see you put in lay-in lines which is a great way to keep structure. The cartoony style works really well with your character! Keep it up!

bold approach - I like it !