Psilocybin, the active chemical in shrooms, is actually slightly more visual then LSD of an equivilant dose, but acid effects sounds more. Music however often sounds amazing on shrooms, and sound seems to have more depth and volume. I can tell my trip has started by looking t the carpet-weird patterns start appearing, woodgrains are very cool. You will also get very giggily.

Only do it with freinds you trust somewhere safe where no one is going to bother you. Get what you need (pink floyd album's, rolled joints, simpsons dvd's etc before hand. Only take them if you are in a good mood and positive frame of mind, and go into the experience knowing it will end in a number of hours (ive noticed a lot of inexpereinced trippers freak out thinking they are going to be tripping for good).