When I design a gijinka I try and achieve 3 things:
1.It's recognisable as the object
2.It conveys their character/personality
3.It appeals to my personal tastes

I always start by asking - how can I get the object's actual design and properties into the gijinka? (Through silhouette, shapes, colour palette, however I can) and in doing so I'm also trying to achieve #2 and #3. That's basically my process - sometimes I'm immediately satisifed with what I come up with and other times I gotta workshop it.
I try not to go too crazy, so real life fashion is usually something I keep in mind, but I do also wing it.

TY for the question it was a good question