Time

One of the most important things is time. You need to make sure that you have not weeks but monthes to make sure that you can have room for mistakes. Remember that a wig could take a month to order and receive.

Example:

This is a long black wig in reasonable price (And a best seller ribbon) for Marceline cosplaying. (I will just use my own hair.) In the purple box shows that when I order it that the wig should be here very soon but above that at the top of the purple box it says it is shipping from China. I have ordered many things from China and bad weather or even confused shippers have caused peices of my wardrobe to go missing in action. So be careful and make sure to make time for items that you will HAVE to order online.