What is a good website for creating t-shirts?

[Jacob Jimenez]

I want to design some t-shirts and want them made. I want to sell the shirts and profit substantially. If anybody knows any good websites they personally have used before that are cheap and good quality, or if anybody has any tips as far as how many shirts i should buy, and how much i should sell. I dont have a set margin for how much i want to make, but i am in the process of planning everything out so nothing is set in stone. i dont have a design but it will not be a basic 3 color scheme. any help is wonderful thank you.