The core aspect to your thought process in deciding which market to chose has to be,

1 – a niche (that is the market) area you know a lot about,

2 – a niche that is popular and you can get a lot of information about to educate yourself on.

A niche that you are interested or passionate in will keep you positive and excited, making everything more enjoyable and not turning it into something that becomes a chore (like the house work my wife expects me to do on the