Not really... just brush (using the long bristled paste brush used for smoothing on initial installation) quite warm water over the bubble area. Once it's fairly damp, use a common household pin to puncture the bubble(s). If the bubble is large, say 2 or 3 inches in diameter, you may have to punture it in 3 or 4 places. Then use the brush to flatten the bubbled area. You may have to work it for a while to get some moisture through the wallpaper to reactivate the paste underneath. I've also used a needle syringe (I got mine from my veterinarian) to inject a little paste through the bubble, and again, brush, brush, brush. I think you could use a well dampened sponge in place of the brush. Good luck!