I'm guessing you just want some advice on how to get a Mimitchi?
On a v1-v3 treat your Tamagotchi perfectly on an EVEN-numbered generation and you will get a Mimitchi (on a v2 or v3, you might not get a Mimitchi, you might get another Mimitchi-level character instead).
On a v4 treat your Tamagotchi decently so you don't get a universal. Hopefully you'll be lucky enough to have a girl teen in the Mame family (Ringotchi or Yangu Mimitchi). Raise the Intelligence skill points so they're the highest. Make sure you do have a decent amount of Style and Kindness skill points too so you don't get a Universal.
On a v4.5 try this: Get a female Tamagotchi and treat it PERFECTLY, just don't do anything that raises skill points, like playing games. I know this will make your Tamagotchi heavy but ignore that. Hopefully you should get a Mimitchi.