I just have to add to the pile saying that a festival is not the right place for your first LSD trip*. The circumstances you have described are just wrong. Please bear in mind that you are ignoring some of the most important advice that can be given to you by choosing to trip (a) for the first time ever (b) without an experienced friend present and (c) in a setting that will be crowded with strangers. The people who are giving you advice have probably seen what can go wrong on an acid trip, and don't want to see you put yourself in a situation where you might get in trouble and not have the right support to get out of it.
The fact that you are so cavalier about your intentions makes me concerned that you might find the LSD experience to be different from what you are expecting. It might sound harsh, but to many of us the only advice that seems appropriate under those conditions is "don't."
Of course, nothing is certain and it's possible that you will be fine. Just be aware that you are exposing yourself to a level of risk that makes experienced users cringe.
* The truth is, I have seen people take LSD for the first time at festivals and have a good, safe time. However, in those cases the festivals were renowned for being drug-friendly, the people in question were under the supervision of myself and at least two other experienced trippers, and they took low doses (about 75 mcg). You haven't mentioned what dose you plan to take, but if you want a piece of advice for your plan, I strongly suggest you keep it low.