@saby
For me, one of the really important things to make sure of is that you’re not leaving any floaters which will end up laying over the top of other people’s ponies during composition.
There’s a million ways to do this. This is how I do it.
A big problem is the little white blobs that are close to the outline of the character. They’re non-contiguous, so the way I learned to handle them was to get as close as possible to the main outline (the black line) and then spam magic wands to grab the debris, combined with “select similar”:
Then I use the eraser, set to HARD, to open a gap between the body that we want, and the background we are trying to get rid of. My default base layer is cyan so I can see it. It really helps floaters pop.
In this image you can see another floater that I had to grab with the wand in order to continue the erasure.
Soon enough you’ve outlined the figures, and can dismiss your mask, set the sensitivity to 254, and if you then click anywhere outside the erased outline you should grab only the background.
Save as transparency, and you’ve got something ready to have the outer edge smoothed, or antialiased if you want.
It doesn’t always work, but for me this is a fast and familiar way to clean up backgrounds.
And, because I’m doing it with a brush on a drawing tablet, it’s easy to “smooth out” spots where the outline doesn’t connect to itself, or where the figure’s primary tone is the same as the background, like under the main character’s arm.
That’s just how I do it - there’s others who can make masks super fast and super reliably.
And you can do the exact same thing by working with the outline instead of the background to create the mask. In this case, the background just was super handy to start with.
Unfortunately, it looks like you ended up with several versions of the same image - and it looks like most of them have got tags for the collab. So you’ll need to pick the one you want to go with.
Please choose which one you prefer, and zap the collab tags from the rest. Or let me know which one you prefer and I’ll remove the tags from the others for you.