Since it's first time, I'd suggest staying away from areas with a lot of people as that can make you feel scared or nervous. Obviously don't drive. It is possible but it can become the most confusing thing once you make one mistake. Grab some glowsticks, get some good music (I'd suggest stuff like Grateful Dead, String Cheese Incident, Sound Tribe Sector 9 a.k.a. STS9, The Doors, Shpongle, etc. Most music will be great if you like it but these are a small few of what I listen to while tripping.) Have some good friends with you. Maybe have a bonfire. Walk through the woods with headphones on or a portable stereo if you got people with you. Do some painting or make some drawings. Play with legos. Bike rides are fun but sometimes gets confusing when crossing roads. Go to a museum or look at some art. Walk barefoot and dance in the grass to music. I'd highly suggest the glowsticks though, they add a lot to the night. And tossing them around to see the trails is great. Any light-up trip toy tends to be cool to look at. If you drink any alcohol make sure you don't drink too much. You can easily drink much more than normal and not feel anything if you're tripping fairly strong. Put it this way. It can make the most pointless things fun. Pretty much brings a childish joy to everything you do. Throw a ball around, a frisbee, or a light up frisbee. You can have a friend drive you around to see the beautiful landscapes, high rise buildings, lakes/ocean (depends where you're at) Sometimes movies can be great, other times they can just be too confusing or hard to pay attention to. Also, generally I don't have much or any visuals if I watch a lot of T.V. during the trip. Will get some peripheral sparks and lights but it tends to greatly weaken the visual aspect to me. Maybe even just sit alone in a dark room and think about some stuff. Maybe read some philosophy before the trip, sometimes it's hard during as the letters might be dancing or melting down the pages. Do what you generally do for fun, and it will be 100x more fun. Play Disc-Golf.
Last and the most important. Always have weed on you. Not really 100% necessary but I love weed, and you may not be able to feel it that much but the smell (if its good) will be heavenly, the taste the same, sometimes it just calms you a little bit other times it does absolutely nothing. For the most part though, it makes it all better.
There are a million things you could do that would be fun as hell, inspirational, life changing, intensifying, etc. The most life changing to me though is good people and great scenery. I used to have little appreciation for art and scenery but the first times I did acid I did it where I could see big rolling hills, mountains, or Lake Michigan. I was able to just sit back, relax, and enjoy all of this beauty. I have been so much more appreciative ever since, I accept people for who they are much better, I appreciate art in ways I never did before, I know how to sit back and decipher what is wrong in my life and make it better. It took acid to get me off coke.