I would definitely take pictures of feet in actual water...but I love the stylization of this.
I can picture this with delightfully thick buttery impasto oil paint, and as an art teacher (K-12) I also have a bit of apprehension. Younger painters can be stingy with their paint. Frugal and mindful of costs.
That's understanding...but a piece of art work IMHO is a bit like birthing a new life, a conception. Every life requires and deserves a full nine month development, for nurturement and the realization of full potential. That is the kind of attitude I believe Christians need to have, (and all good artists for that matter of all faiths and persuasions), but we especially wishing to be lights and examples.
If God is indeed calling us to the arts, then we are yet lights in a dark place. No stingy attitude....no room for it. Even if you have to do brownie and cookie bake sales! Get the resources you need.
If you are going to do it in acrylics, get some Liquitex Extender Gel Medium and mix almost half to half with colors. It will give the acrylic body and thickness somewhat like oils. It captures light more textured and as a body of paint and comes off more jewel like in color brilliance.
I can already imagine the near post-Impressionistic expressionistic application here of gorgeous full bodied paint. Wonderful!!!!
Give the project 110%....