I've attached a link that explains the process pretty thoroughly.

Be sure to read the second paragraph :-) Seedling grown JM's may or may not bear any resemblance to the parent plant and cannot be referred to by that cultivar name. What you may produce will just be generic seedling JM's, although if you are lucky, you may get several that may look quite similar to 'Fireglow' in appearance. But no guarantees.

Here is a link that might be useful: JM seed propagation