Want to try add ridges to my concave XMD Galaxy Mega

[s18067]

I need some advice on what to do, especially materials - wise. Should I just use normal putty and corn or the way I want, then glue it on the pieces? Or should I try some other approach? I miss the grip of my old dayan with ridges. I wouldh've gotten the sculpted of it wasn't stickerless, which is useless for me.
Any ideas or suggestions?