Can i write my own contract stating artwork that i sell includes the rights to it?

i'm starting a graphic design company, creating logos and such. i need to have a contract for my clients stating that when they hire me to create a business logo for them, they also purchase the rights to that logo. it needs to be clear to them that, once they purchase a logo from me, they can go out on their own to pursue copyrights and trademarks without any further involvement from me. can i write my own contract, print two copies, and both the client and i sign it? or does something actually have to be drafted by a lawyer? if i can write my own, what are some specific information that i should include? thanks.