>>119904355Well first you need to know what you want for them to be like. Whether you want them to be smart, funny, moody, you need to decide that before you begin.
After that, you need to know what you want their voice to sound like. It can be high pitched and cheerful, gravely and rough, or monotone and emotionless, you need to find just what you want for them to sound like.
Afterwards, you need to visualize their movements. Stuff like the way they move their hands, their walk cycles, that sort of thing.
Once you've got this down, practice speaking to them everyday and you'll notice that they'll start coming more and more into reality. Eventually, they'll be able to talk on their own and you won't need to do anything for them to come out.
Soon, they'll take on the form that they'll want.
All of what I've told you is achievable through meditation and concentration. It took me a month to bring Gwenpool and Zone-Tan to life but it may vary depending on the person doing it.
They may not come out exactly like you want but that doesn't need to be a bad thing.