It's best used neat with a lint free cloth, it will evoprate off as you wipe the record. If you use it neat you do have to worry about spilling any on the label and getting "water damage" .You can buy alco wipes that are for cleaning skin before injections that contain isoproply alcohol on a little square of soft cloth which are useful if your out and about DJing and get crap on a record.
Two thing though, DON'T smoke etc as it very flammble and DON'T get it any where near your acetates as it will melt them!
If you got a really hissy disk you are record to CD etc, you can litteraly soak it in isopropyl alcohol and playing it thus will markedly reduce the noise.
If you've got a really shagged, dirty record that you want to spruce up and sell to some poor unsuspecting mug, you can use WD40 (watch the label!), works very well but stinks!!