I forgot the most important thing. Before you chose a poke, make sure that you have actual experience with most of the pokes's sets. So if you want to reserve Deoxys-D, make sure that you have experience with his 2 most popular sets, the fast spiker and the suicide spiker. It would be very beneficial for you to make some offensive teams (Deoxys-D works in bulky offensive or all out offensive teams) and try out his potential, and then, yes, you could try and do his analysis. Just prepare for the worst, because this is your first analysis, and it might be locked after a while, due to low quality. This won't be your fault(if it happens, i don't want to scare you), as no matter how much effort you put, it is just logic that a new member hasn't get used to how analyses are written and presented...
Anyway gl, and if you want anything ask me!