Here's a male and female version of my most horrific Steele.
That are terrifing 20 somethings...
If you could use the existing mods in the game to make the most terrifying abomination your twisted mind could possibly think of, what would you do?
Anyways, I guess the serious awnser is 'eat everything' and do not savescum. Mainly, native foods. find some of the more rare transformatives with odd goals, like being a plant and take one or two of them, too.
The goal is to become a mess of species, the game should be unable to describe you as anything but a alien being. Throw in some early thing to be a herm and get transformations locked behind gender in some cases.
There are a few things, however, one should avoid: taking to many of a thing since it yould 'clean' you, some specific transformatives (mainly things that you can buy) making you too vanilla, galo-max... The usual things.