Much more because I tend to forget these things all the time than anything else:
Certutil -Setreg Policy\EditFlags +EDITF_ATTRIBUTESUBJECTALTNAME2
NET Stop certsvc
Net Start certsvc
then you can create a INF file with the following:
[NewRequest]
Subject="CN=<your real hostname here>"
[RequestAttributes]
CertificateTemplate="<your templatename here>"
SAN="DNS==<your real hostname here>&DNS=<hostname1>&DNS=<hostname2>"