Some people just use Baby Powder, but I'm here to tell you unless you are using organic talc free it has some nasty stuff in it. There are a myriad of different recipes and some people just use cornstarch, but I wanted mine to be a shade closer to my skin tone so my main ingredient is oatmeal flour.
Here is the recipe:
1/2 Cup Oatmeal Flour
1/4 Cup Corn Starch
1/4 Cup Baking Soda
I wanted a shaker, but don't have any of those parmesan cheese ones, and wasn't going to buy something when i'm sure I could modify something I have.... So I used a small Mason Jar. I made a circular pattern with a nail and tapped small holes into the lid.
If you don't have Oatmeal flour (because I know I didn't) you can make it yourself. Just use your spice grinder and blend some up. This is by far the easiest way to make your own flour (oatmeal & rice). You could also use a food processor, but this is better for the size you are making.
Grind till it's a fine powder.
Stir your ingredients well in a bowl.
Transfer to your jar. If you are going to be traveling just sit a lid with no holes on top and screw both on, this way none spills in your bag.
I took this with me on Jess and I's road trip to RI. And it worked like a charm. I'm now obsessed, because it gives my hair such great texture I can style it way more than when it is freshly washed.