I'm sure you've already got plans to take your youth group to an amusement park, raft trip, outward bound camp, and/or a mission trip this summer. Summer is only about twelve weeks long so you want to pack in as much as you can while the weather is nice and the kids have the time. It is also important to plan a few spiritual retreats for yourself.
My favorite activity is camping. I go by myself to a favorite spot. Two nights is enough for me. That allows one whole day for prayer, reflection, and relaxation. The prayers are frequently "listening" prayers. The hikes, fishing, reading, napping are things I do for refreshment feeling that God is doing them with me. It's great to be surrounded by things God created.
I am able to do this because our church traditionally does not do Sunday school on the first weekend of every month so I can be gone. I also have a team of practiced helpers who can step in and cover the days I miss.
My wife also does spiritual retreats...alone. She usually has her spiritual retreats in a condo she gets through a travel club for just $99.00 a week (e-mail me and I will refer you to this club). That's cheaper than camping. It gets her away from the distractions of home. She also feels safer than being in the wilderness. Plus, it gives her the opportunity to go in bad weather or the winter. She takes her favorite music, devotionals, and easy food. She goes for a week at a time, comes home really refreshed.
Whatever you can do, plan to do it before a hectic schedule crowds it out.
If it's already too late for that you can still get a little time for yourself and be a great example to your kids at the same time. Jesus frequently left his dusty band and went off alone to pray. When you're on an outing with your kids just let it be known that the first thing in the morning, for about an hour, you'll be walking a little ways from camp to do your own "quiet time." Suggest they do the same (safely). My son actually does this when we go camping together. What a witness it has been to me. A pastor friend also does this. He goes camping every week, invites guys to join him, but it's understood that he will be doing his quiet time every morning and highly recommends those who join him to do the same.
It's commonly know that "more is caught than taught" in youth ministry. The kids will remember seeing you making your time alone with God a priority.
I can't stress enough how important this has been my for continued spiritual health and vitality. When ministry starts to feel overwhelming it's usually a reminder that I need to get alone with God to pray, listen, even cry and complain. Burnout is one of the most frequent topics in the youth ministry forums I participate in. There are many reasons youth pastors and leaders give for feeling burned out. These reasons are just symptoms of the underlying cause. The real cause is lack of spiritual nourishment.
You can't remain a healthy branch of you're not constantly sucking nourishment from "the vine."