Firstly, understand what is COSPLAY... search through wiki or sort..
Cosplay is basically costume play.
Where you get to put on costume and portray the character.
.. cosplay is cosplay
Secondly, list out the reasons why you want to cosplay.
This can help you to find your main objective to cosplay.
..because I love to DIY stuffs
Thirdly, decide who you want to cosplay.
actually I do really encourage you to choose your most favorite character.
but since you're still new.. just choose those character that is simple would be fine.
..I started off as high school student.. Inoue Orihime
Lastly, do research.
Understand your character.. their characteristic, outfit, behavior, poses, etc..
.. I actually did research on cosplay for a year before I actually joined in XD