The best way to deal with/prevent punctures on tubular tyres
You could try adding sealant to your tubular tire.

Tufo Tire Sealant, Stans's No-tubes (and other tubeless sealants) can be used to deal with small punctures. Most recommend not using the sealant as a preventative measure, but more so as an after the fact solution to quickly fix punctures on the road.  

However, Tufo Standard tire sealant says that it can be used as a preventative measure, but I can't speak for this. I've heard that it could affect ride quality, so it may be best used in a roadside emergency.