Someone said :
I have drawers full of wigs I love unnatural colours and over the top stuff but I think I love my real here more so (currently icey blonde which was supposed to have pink streaks but the pink didn't come out right it came out even whiter which is okay for now but I'll fix it on Tuesday)
What brand of dye are you using? I dye my hair a lot and no mess for colours like blue, green, pink etc the best brand is "Live" because the good thing about it is it doesn't come as a whole kit that you have to fap around with, it just comes in a tube kinda like a tube of paint so say I wanted to dye my whole head blue (like in my profile pic) I'd use 3 but if I only wanted streaks I'd probably only use about half a tube (it covers really well too) and then you can just put the lid on it and use it as you need to do touch up's. You can get it in Boot's (I think they are the only pharmacy that stock it because I haven't seen it anywhere else) and the larger the Boots store the more colours they stock so for you that would probably be the Boot's in Jervis Street shopping center.
These are all the colours they stock (I'm thinking of going for the Shocking Pink one next) https://www.boots.ie/schwarzkopf/schwarzkopf-live