I took 4 years off back when I was at university, I was a low single digit handicap when I hung up the clubs. Came back to it when I got out of school and hit the range for a couple days, did quite a bit of short game practice to try to get the feels back, then just started playing. First thing I did on the range is check the fundamentals, setup/alignment, etc. The important thing is to not have any expectations about being at the same level as you were before the hiatus, just enjoy the walk/ride on the course, enjoy the weather, hit shots as best you can and celebrate the good ones.
On the range, make it more than just beating balls, make a game, switch targets frequently, try to hit different shots, play holes (hit driver/wood, iron, then maybe a chip/pitch shot). Same thing on the practice green, make 18 par 2 holes and see how close you can come to par. Good to mix it up too with putts, give yourself some realistic chances at making a 1, mix a few chips in there.