Start with the people. The people are very important. They have to be the right people, but you will know who the right people are. Their faces will be burned into your retinas, the sound of their voices laughing, crying will be with you for the rest of your life.
All good memories have a start and an end. Figure this out early, timeboxing your memories is key. Maybe it is a weekend, or the length of a trip. Maybe it is a single night. The window, the time to make your memory is only as good as knowing when it is up.
When the time is up, let go with speed and grace. Do not hold on for too long, do not drag it out. Turn around and keep walking. Cool guys do not look back at explosions. Know that while you wish things could go on longer, the sooner this time ends, the sooner it will be there when you need it. A great memory can keep you going through the worst of it.
Give the time a name. All important things have a name. It does not have to be a good name; as dumb as "Spring Break '97" sounds, that dumb name might be enough to bring you back to that bar beside that beach with that boy at your side.
Create your inside jokes. Find them early and pounce hard. Repeat the same dumb phrase until you find it funny, then until everyone finds it funny, then until it is so funny nobody can breathe. Go up to strangers and say "sluicebox" or "frigid dick" and laugh and laugh and laugh because you are there and everyone else is there and in that moment it is the funniest set of words in any language.
And when it is over, never speak them again. Think of them often, but to repeat them outside of their time is to lessen their power. Cherish them, remember the feeling of being brought together by these simple words. You will need the warmth that these words provide, keep them sacred and ready in your time of need.
Let yourself be the person you wish you were. Let go of everything but the moment, this moment, this moment, this moment right now. Forget consequences, those are for after this time. The more you do this, the more everyone else will too, until it positive feedback loops forever. Say yes to everything. Go there. Kiss the girl. Dance. Always dance. When the music stops, make your own music. Never stop dancing.
Take pictures. Lots of pictures. How you capture your memory is up to you, but anyone who says "stop taking pictures and start living" has not fully grasped the power a great photo can have. After the time is up, these photos are going to be key to ensuring this memory remains as great as it did in the moment. Print them out, as big as you can and put them everywhere you can see them.
(The only exception to this is no cameras on the dance floor. There should never be cameras on the dance floor.)
The most important part of making a memory is that you can never repeat it, so it is very important that you not try. At the same time, it is very easy to lose yourself in nostalgia. Entire nights with those people, recounting that time, remembering when you were that person.
You are better than that. Your memory was good? Top it. Take what you learned, take the person you were in that time and improve upon it. Make another memory, a better one. Start planning now. Better to be looking forward than back. You can only go up from here.