In a pipe, smoke it in one shot. And keep the smoke inside for at least 15 seconds.
Be careful, it is really strong. Effects can vary widely between people. I am one of those ''lucky'' people who always hit me hard. It takes me about 8 years to forget how much panic I felt and smoke it again. A gram of 20x is a lifetime supply for me.
I tried to smoke really little, and even if it was not so absorbing, it was definitely not comfortable.
I don't like it much but it is quite impressive where it can take you. It is the most feared psychedelic I ever tried. Wish there was another method than smoking it, I don't like instant onsets.
Forgot to mention, you should have about 40 doses in a gram 40x. So 25mg.
There has been some talk about if the normal dosage of salvia is in fact overdosing. I don't think it is dangerous physically, but you could explore lower dosages to get to know the mental space.