Oh, I forgot to add, yes you can say, "I'm going for a tattoo soon." But I'd probably say, "I'm getting a tattoo soon. I'm going for shopping soon" is not correct. I'm going shopping. I'm going to the shopping. But you might say, "I'm going shopping for a new coat." I'm going for a beer" is commonly said! And, "I'm going for a pizza."

Mostly we would say, "I'm getting a tattoo soon" and "I'm going to the tattoo parlour in town." In general: I want/would like a tattoo; I'd love a tattoo but my parents won't let me; I'm going to get a tattoo even if my parents disagree!" Some grammar: If you say "I'd like to tattoo..." this suggests you want to tattoo someone else. If you say, "I'd like to tattoo myself..." this means you want to tattoo yourself! You want to do it to yourself - which might be difficult! If you use the passive, it makes more sense. "I'd like to be tattooed by Mr Smith. He's so good at tattooing." You can also say, "I'm getting myself tattooed/having myself tattooed." Afterwards you'd say, "I was tattooed at the parlour/shop in town by Mr Smith." Or, "I had/got myself tattooed." And "I got/had the tattoo in town." "I got/had my arm tattooed." More examples with the verb 'to have.' I'm going to have a tattoo (done) on my arm. I have a tattoo on my leg. I had a tattoo (done) last week. Just check the meaning: who is doing the tattooing and who is getting the tattoo!

Oops, that should be, "I'm going to the shops!" not to shopping! I actually DID have my glasses on, so I guess it was my brain not working. Need more coffee!