Tosser = idiot. Dummy.
Shite is more polite than shoot. It's also a way of getting round the swear filters
Hell and dam are great.
From my Irish mum and some of my Irish friends. " Feck" is quite a mild epithet, wheras" F*ck" is quite harsh. " Feckin Eejit" is almost a term of endearment when you've done something daft. My favourite is " Gobshite" and " Feckin Gobshite" which I apply to most politicians uttering 😉