Homemade Nail Buffing Cream?

I haven't tried it, but I suggest coconut oil, olive oil or any other kind of good oil.

Actually, you don't need a nail buffing cream just a gentle nail buffer. It's the buffer that does the buffing ;-) You also don't want to do it too much or too often or you will wear away the nails which will weaken them. No nail cream will strengthen the nails (they are a dead appendage) but eating a healthy balanced diet will help strengthen the nails that eventually grow from the cuticle bed.

A little bit of baking soda makes a great buffer.

One part bees wax, two parts oil (coconut, for instance) - melt.