Tip: Shellac is a great way to seal your armor to protect the paint. It dries fast and is very durable. I also add bits of velvet fabric into spots where the armor rubs together to cut down on paint abrasion.
Tip: Always double check your connections! It is very important to really think about how you are going to attach armor to your body. The worst thing that could happen is to go to a convention and a few minutes walking in all of your armor starts to fall off! To trouble shoot this I use clips, buckles, d hooks, velcro, elastic, and even magnets. Don't forget to pack zip ties in your emergency repair kit if any of these connections break. This has saved me in the past!
Tip: Practice putting on your make up before you go to a convention. Putting on make up for a costume the first time can be a bit of an experimentation. It took me three tries before I was able to figure out the technique that I liked for my Death Knight. Each time you practice you will learn more about the products you are using. I give myself at least an hour to put on make up. Take your time, don't rush, and finish your awesome look with a sealer!
Tip: Remember to have fun! Don't be afraid to try something new and be yourself. I made my Entei Legendary Pokemon armor just for this reason. This was my first original design and it was a very different experience than what I am used to. When competing, I try really hard to maintain accuracy on the character, however on this build there was no reference photo. I took artistic liberty and just made it up as I went! It was such a liberating experience and has helped me grow as an artist.