When camping at Festivals, you'll be walking around during all day, so you'll want to make sure you get a good night's sleep so you won't be tired the next day. So, I'll introduce some goods to help you sleep comfortably!
Just loosen the valve and it will automatically inflate, making it easy to set up. It inflates firmly with urethane and air, so you can lie down without feeling the unevenness of the ground. Because it is thick, there is no pain when your back hits the mattress, and you can easily roll over. It provides a level of comfort that cannot be obtained with silver mats alone. The back of the mat is treated to prevent it from shifting, which is also a nice touch. If you are pitching your tent on a slope, please be creative with your luggage.
Once you have a good mattress, the next step is the pillow. Many people use their luggage or a change of clothes in their sleeping bag as a pillow, and I have done the same. But my neck and the back of my head still got a little tired. This pillow, like the aforementioned mattress, can be inflated automatically by loosening the valve. It is made of low-resilience polyurethane foam and is comfortable to wrap around. You can also adjust the amount of inflation and height by blowing air directly into it.
This cot is very light and easy to assemble. When camping at festivals where there is a sudden downpour (during Fuji Rock, for example), it is useful to have a cot to keep your sleeping bag and luggage from getting wet during flooding. Even if you don't have much space in your solo tent, you can put your stuff under the cot. In that case, put them in a plastic bag to keep them dry. If you have a low tent, though, the ceiling will be too close.
When choosing a sleeping bag, it is important to carefully check the minimum temperature for the season in which the festival will be held. If the festival is held at a high altitudes, the nights will be cold even in the middle of summer. And when choosing a sleeping bag, be sure to look at the comfortable temperature rather than the temperature limit. When I was young, I once chose a sleeping bag based on the temperature limit without doing much research, and it was a painful experience. And that time I was using a silver mattress. It's hard to sleep when you're cold even when you're dressed. It doesn't matter how young you are.... When choosing a sleeping bag, it is best to go to an outdoor store and see and touch the actual product. If there is anything you don't understand, talk to the clerk! If you want to know more about it, search for "European Norm" and you will find a lot of information.
If you are not able to reduce your luggage without using heavy options, I recommend that you just try a little harder with your mattress.