Perhaps the nicest thing ever happen in KLIA is the introduction of self check-in. We got the opportunity to try out last week and we were pleasantly surprised that it is so easy to use. Actually, one MAS staff was there helping to explain if the need arises.
They have two rows of these machines at the domestic check-in counters. I didn't check the international side.
You have a choice of BM and English. Get to choose your own seat, and then print the boarding pass. I like the choosing of seat and my children simply love it!
After the boarding pass is printed, just bring the check-in bag to the counter and check-in.