Check out some of Luke Vernon’s videos on youtube. You’ll get some good insights from that.
I find it alot more laid back than the UK, especially if you are coming from Southern England.
Some things to note
The rules of the road are almost the exact same as the UK except speed limits are in Kph and sometimes absurdly high. On most major roads there is a hard shoulder marked out by yellow lines, your allowed drive in this to let traffic overtake but watch out because there’s usually people walking or cycling in them.
The motorway network connecting Dublin, Cork, Belfast and Limerick is pretty good these days but there’s very few laybys or motorway services. If you need to stop for the night then you will probably need to come off the motorway and get onto the ‘old road’ the nearest village should have somewhere. The only two proper motorway services I know of are North of Dublin at Lusk and Castlebellingham.
Be particularly wary of diesel leprechauns in the midlands.
If your not traveling between the major cities above then your in for alot fun especially in the west. And mind the bridges, you usually don’t know about a height restriction until you can actually see the bridge you’re gonna hit and then there’s nowhere to turn.
Driving standards are better than they were but still crap. In the old days all you needed to drive in Ireland was a theory test and then you got your provisional and drove around unaccompanied. They’ve actually started to enforce the law a bit now but there’s still people with a full licence who never passed a test because of an amnesty back in the day ( people were waiting to long for the test so they just gave them licences 
)
Lastly if your going over the border get your euro’s or sterling in plenty of time because its not always obvious that you’ve gone over the border until you stop at a service station and get chased out for trying to pay in the wrong currency. ( I tried to buy a sandwich in rural northern Ireland with a 5 euro note once and nearly got lynched 
)
Other than that nice little country, think Scotland only a bit crazier.