If you want it do it, don't do it for other people, do it for your own reasons.
If you have social obligations in which a Tattoo would be inappropriate put it where it is private for you!
On your forehead it sucks and you would look like an idiot.
Ink is personal, millions of surfers have tattoos.
If you are doing it to impress IMO it's a fail, with a shaka visible you would need to have the surf ability to back the sign.
Tattoos are so commonplace now they are just background.
Make sure if you get one it is well done, bad ink is awful!
Consider and go back to the first sentence

I've taken up troll hunting just for fun, instead of a rifle I'll just use a pun! 冲浪爷爷