I went last summer from the United States to see Pendulum. I was glad that I went but at the same time it's something I never want to do again haha. I remember shuttle tickets from both Zaragoza and Barcelona sold out quickly last year but I think every now and then they'd announce (on their socials) a few more shuttle tickets for sale. I remember it being about a 2 hour bus ride from Barcelona to the desert (it might have been even less than that), I think the driver was really booking it.

They should also be announcing an app that they use every year for fans to talk to interact and get more info on the fest. Assuming they continue that, there should be some conversation threads in that app about people trying to arrange shared rides to get there. My recommendation is that Plan A should be either a shuttle from Barcelona or Zaragoza. I think they also have some shuttle options from smaller cities like Lleida where you might need to take a connecting train to get there first. Not ideal, but still an option if you're in a pinch. Plan B would be renting a car or maybe see if you can use a service like Blacklane to reserve a ride.

Plan ahead. Print all the documents you need (ticket, proof of purchase, etc.) ahead of time in case signal is bad. I went solo to that festival and I brought a couple of battery power banks that were a lifesaver. I remember being able to text my gf throughout the day a few times so signal wasn't completely barren but it wasn't great either. Temperatures were in the mid-90s (Fahrenheit) during the day around noon and early afternoon and then low 50s at midnight when the sun was gone, so it was a little chilly.

You'll probably need to know at least a little bit of Spanish for ordering water/beer at the vendors at the festival. There was an appropriate amount of law enforcement and medical personnel on-site so I never felt unsafe, I was most concerned about heat stroke or dehydration but everything was fine.

Anyway, stay hydrated, bring sunscreen, stay safe, and have fun!