How would one make a concept for a character one knows well but has no idea how to do it? I would like one concept for Spock from Star Trek. But I don’t think it’s possible.
Thank you for reading
As one said “Live long and Prosper” 
If you want you can use this scaffold I made for creating concepts.
Try planning out some abilities and see what works best.
How does one choose color team for Trials? Or is it randomed?
It’s up to you. Think about what colours the character is associated with.
You can choose, like, if Negaduck had a red cape and a yellow costume on, you could pick red.