You don't need to make cannabis oil to vape?
Unless you mean you want to do dabs. Which i guess is technically vaping.
Anyway, It can be dangerous - especially if you don't know what you are doing. depends on the solvent you use as well. I used to make shatter for medical dispensaries - so I could give you a run down but I'm not exactly sure what the rules are regarding this topic and I don't want to post anything I'm not supposed to. If you're really interested you could PM me and when I have some time I could type of a simple/relatively safe method.