Can I thin mod podge with a little water?

yes

depends on your project

yes

Definitely-good idea!

Why not take a look at my project: This is a thinner podge.

https://www.hometalk.com/diy/paint/mom-podge-the-mother-of-gesso-and-modeling-paste-34374501

why is it when I am doing my glass plates with modge podge it still looks milky after fabric is on,i done a few plates that didn't do that why is it now?

I was wondering the same. I’m making shoes covered in glitter to be thrown from a parade float during Mardi Gras. This is my first time doing this and I’ve tried sealing the glitter with a spray can of clear coat and it just doesn’t do the trick. I’ve just covered one shoe with mod podge and it just seems super thick as a sealer. They won’t be worn, but they do need to last long enough to make it through a parade and into the hands of its new owner. How much water should one add? Would half and half work?