What I generally do is mix different costumes that the character has worn to get the final product...like look at my avatar right now, it's a mix of old Blink and new Blink! 3nodding
My original Blink TekTek:

AoA Blink:

Mimic:

Nocturne:

Namora:

Namor:

Moon Knight (Completed):

Typhoid Mary:

Callisto (Completed):

Wolfsbane (Completed):

Super-Skrull Rogue:

Skaar:

Hepzibah aka The Most Expensive Cosplay Avatar Ever:

More to come....