Driving to KL is extremely easy. Once you take the 2nd link, its just one straight road all the way, with very clear signs.
On the return, don't expect any signs saying Singapore. When you leave KL, you will usually see Seremban, then Melaka and then Johor Bahru. Only when you are very close to Singapore, you will see signboards saying Singapura (Tuas).
You can take a look at this website for more info and maps etc.
http://www.plus.com.my
Some tips :
1. Try to stay in Lane 2 unless overtaking. The speed limit in most places in 110kmph. It can get quite boring after a while and you will be tempted to go faster. Many of the cars driving in Lane 1 go at 150-160kmph. If you drive in Lane 1, you will have to keep watching your rearview mirror every minute and then filter to Lane 2 as there will definitely be a car on your tail within minutes. They just come out of nowhere :bsmilie:
2. Be aware of strong crosswinds in certain parts of the highway. There are signs that warn you of that.
3. Get adequate rest before the drive. Stop every 2 hrs along the way, if you are not used to driving long distances. Both the engine and your body need a break.
4. This is a tip which some friends of mine passed on to me. Hope you never have to face such a situation. If at all, your car is hit from behind (or even touched), don't stop to inspect the damage and instead drive on. I heard that this is a classic way of carjacking employed over there.
5. Have enough Malaysian Ringgit on hand. All the tolls accept only Malaysian Ringgit. Also, don't go into the right lanes of the toll booths. They are reserved for the Touch n Go (as in prepaid cards) method of paying the tolls. Use the left most lanes - which are meant for cash payment.
6. There are lots of R&R stops (I guess every 20-30 kms or so) with usually clean toilets etc. So, no reason for you to stop anywhere on the highway. Stop at one of these R&Rs.
7. The last toll booth you will hit before you enter KL is the Sungei Besi toll. You can easily spot this. There will be the Mines Resort and Palace of Golden Horses Hotel to your right.
8. Check with the hotel where you will be staying in KL and get the directions from there to your hotel. Driving in KL can be quite difficult if you are not used to the roads. Better to park your car in the hotel and use taxis.
Hope this helps.