Sonic: What happened?
Tails: anda fell from the sky and was unconscious! Are anda alright?
Sonic: I'm fine but...Who are you?
Tails: I'm your best buddy, Tails.
Sonic: I haven't seen anda before in my life.
-Tails felt kind of heartbroken, hearing that from his best friend and brother, but he knew Sonic lost his memory. He could probably regain it sooner atau later.-
Knuckles: anda seriously don't remember, do you?
Sonic: No...Should I?
-Knuckles and Tails looked at each other and then explained how they met and about Eggman and about Sonic is always stopping him.-
Sonic: Sounds tough. And I can really run...

We've all tried to make an OC (Or I assume we have) Anywho, there are many people who just can't do it. First thing to do is NOT the appearance. I know, it's tempting as all get-out, but trust me. It's better to get the character's personality and such down first.
First, anda should have a general idea of a character's past. If anda get an idea like 'flying kadal monkey' (Not advised) Then jot it down. I hate when anda have a great idea, and end up losing it while thinking too hard on how the character should say stuff atau whatnot. If anda jot down one sentence about them, then anda can refer to...