I don't keep sailfins, but I have kept waterdragons for many years.

From the only site I could find at the moment...here's how they say to incubate sailfin eggs...
http://aquario-terrario.superforum.fr/Terrariophilie-c4/Fiches-techniques-f24/Fiches-techniques-Sauriens-f43/Basiliscus-plumifrons-t125.htm
"Incubation sur substrat humide à 30°c et 80% d'hygrométrie"....even though its French I'm sure you can understand that the temp. is 30C and the humidity is about 80%.

Good luck! Sailfins are beautiful animals.