It depends on what you mean by "edge lift", there are different kinds of warps and it depends on whether it's a heat warp, etc.
I don't think anyone should play with record flattening themselves (especially on expensive records). Find somewhere that has a machine and try that, even that is not foolproof but it's way safer.
Finally, if you do want to do it yourself, you could buy this thing:
https://www.vinylflat.com/
I haven't used it and have not heard of anyone's experiences with it.