Aloe or lotion as often as you can. Keep the skin moist so it can heal. Unfortunately it's a waiting game.
If your sunburn is really bad, Solarcaine helps with the pain. I would caution using too much though as your skin is more permeable when injured and the product contains lidocaine.
Stay hydrated. Take some ibuprofen if you can't handle the pain. Avoid re-exposure to sunlight of the affected areas until healed. If you can't avoid it, then apply sunscreen at minimum SPF15, 15-30min prior and often while outside. I prefer to just use the SPF50 since it provides the maximum protection. Anything above is just marketing hooplah.
I had the horrible experience of making foolish mistakes fishing one day that led to my entire torso covered in blisters. I had to sleep on a towel on my back and it took a week for my skin to tolerate any clothing....