Just buy a splicing book from Samson and start learning. Once you learn how many different kinds of rope there are, and how the different splices work, it will come pretty easy. I like to splice while everybody else is watching some wretched show on tv that I don't really care for. Keeps your hands & mind busy, while still participating in the family "sit down & relax" time.
Splice some old beater rope, then try to destroy your splices. It will build confidence and a lot of understanding. Don't worry about trusting your work, that will come with time.
The biggest part about trusting splicing is a good understanding of how they work and why they don't come apart. Until you have done a few, you won't understand, so you won't be able to trust them.
I don't understand how anyone can trust a "pro" splice until they know and understand the splices themselves. That is like trusting the airplane to fly without understanding what the wings do.
BTW: No, I never bought a commercial splice until very recently, but I have been splicing for years.