You have to breathe in as much smoke if you can, then hold it in your longs as long as you can (I usually count to 30, to hold it in for about 30 seconds), maybe let go a little smoke, and then breathe in again, trying to hold it as long as you can. Then take another hit, doing the same thing.
Try to do it in a place you cannot get distracted, closing your eyes could help too, and maybe you should meditate some before you smoke it.
Maybe you did it the right way, then you are appearently really tolerant of salvia. A lot of people experience that the more they use it, the less tolerant they are, this goes for me as well, but as I said, some people are extremely tolerant of the substance, you could be one of these people.