I would agree with much of the advice given here, as far as being patient and doing your homework, but in my experience, starting with small doses hasn't always given first-timers the best results. I am CERTAINLY not recommending that you take a very high dose without ample preparation; I have no desire to wish that kind of terror upon anyone, but I have found many times before that after first timers get a taste of what they're dealing with, they are very afraid to go back. This happened to me after my first time and it took me many many months until I mustered up the courage to try it again, and I was greatly rewarded and praised by the entities there for having the nerve to come back. They seem to like courage.
Terence McKenna has said a lot on this subject, when it comes to dosage and sometimes doing too low of a dose. He says something along the lines of "Don't diddle your dose! Do your homework, do the research, and go for it!"
When comparing my first time use (as someone with quite a bit of LSD use under their belt), to some of my friends' first times (without nearly as much 'experience' in the psychedelic world), I have found very inconsistent results. The first time I smoked DMT (broke through), it scared me so intensely that I can't even describe it (though many here probably know what I mean), but some of those "less experienced" friends of mine broke through on their first dose, and came back crying tears of joy at the beauty of it. Part of me wishes that I had started low and worked my way up, so that maybe I wouldn't be as terrified of it as I am now, but not everyone is like me.
The truth is, no matter how much you prepare, research, study, etc. before you try it the first time, you CANNOT be ready for it. It will knock you off your feet and rattle your foundations no matter how many other psychedelics you have or haven't used.
There's also the risk of doing small doses, thinking to yourself "well this isn't so intense..." and then upping your dose dramatically, with very uncomfortable results. The elves don't take kindly to an attitude of "well this isn't that crazy after all" and will go out of their way to show you otherwise. So if you do start low, do it consistently. Work your way up slowly, and realize that what you see at low doses STILL won't prepare you for what you're in for.
But before any of this, READ READ READ READ READ
Just because you can't be fully prepared doesn't mean you shouldn't try to be less unprepared