Salvia is nothing like LSD.... completely different substances, that affects completly different receptors in the brain...
Salvia is intense in the fact that reality goes bye bye and your thrown into a whole new world...
Acid is intense in that reality and your perception of it warps, your still in visual touch with reality but things move, shift, and form patterns...There is a large mental aspect to it as well, time slows down and your thoughts speed up to a degree you probably never thought possible.... you can close your eyes and just think for what seems like hours only to open your eyes and see that a couple of minutes have passed.... Confusion on LSD is kind of how you look at it, my first trip i felt like i had the answers to everything, a bit of megalomania... but i also could not remember what sanity even was, but i knew that whatever it was it would be back by sunrise so i just stopped worrying about my state of mind and enjoyed it...
As for the amount of control, you have more with LSD than Salvia, but all in all its best just relax and let go...
After its all said and done expect a few things, assuming you have a good trip, after some food and sleep expect to feel that life is good. If your have a powerful first trip and you probably will given its your first time and you have no idea what it is, even a small dose will be powerful, your probably going to be a little bit mind fucked by the whole experience. With me i said hardly anything for the next 3 days after my trip, i was shaken and had to piece everything together. Its interesting when someone ask how was your trip and words don't exist to describe it...
Acid is my favorite drug, it was my first psych and i can say my first acid trip was the most amazing experience of my life. I highly recommend it, find a friend and do 2 each. 1 will probably get you a decent enough experience but in the end your probably going to be thinking "i wish i had done more"...