We've found that Serama hatch rate on USPS shipped eggs is very low.  Air sacs get loosened, and these wouldn't hatch.. But we did get some to hatch and have six wonderful young Seramas (adorable all!). Some came from nice people here (we're very happy & grateful)!
You may want to practice hatching "normal" chickens first, as we did (Leghorns) and sell or give them away if you don't want them.  We have 4 Leghorn pullets that we kept - very nice birds - we're very happy with them too (and just starting to lay!!!).
my Wife had to "rescue" 2 serama chicks in hatching  - 1 pipped upside down - and one just was stuck and weak - because we had at least some experience  and because of great advice on byc regarding when and how to help chicks hatch - my wife saved these 2 - which otherwise would have died.
It's hard enough to hatch normal chickens, so do practice!!!!  Also do read up here on byc because you can do more harm than good in trying to help a chick hatch - unless you have great advice (and there is so much great advice here!).   Good luck!