I wish I could give you some incubating tricks, but I cheat and have an army of bantams for broodies. Sometimes I have them start eggs for 10 days and put them in the incubator to give them a good start.
If you get eggs from seramas smaller than a B class bird, you incubate them the same way. Just make sure they are not pullet eggs and in good shape. Usually the tiniest of the serama hen's dont lay as well, but if your friend is getting eggs, take them. The small birds can produce larger chicks, and the B class birds can produce A class chicks (or micros) too. I prefer using a larger A hen or B class hen with an A class roo, if I have one I like. The B class hens just lay better, and seramas produce a range of sizes. Check for infertility in the very smallest of the birds if you breed some later.