I like a nice big bag to carry all of my prep needs for castings, and shoots.
I hate carrying things I DON'T need. Here are some tips for 5 things you can easily get that are important for your modeling castings.
Travel size creams and lotions are great.
Panty hose. Keep an extra pair in your bag or in your drawer
Hair ties and hair clips.
Clear nail polish
These items might not be the first thing on your mind when you think of modeling but they do come in handy!