How is the "pushing" of the domain usually done? If I wanna buy a domain from someone on the forum here or somewhere esle and pay through PayPal, how do I get the right for the domain?
After you pay for the seller, they will push the domain to your account, then you will have the right for the domain. But if you buy a good domain with big $$$, you should buy it through some agent, i did one through Sedo with amount $xxxx
You will need an account set up with the same registrar that they have, eg. if the name is with Name.com then you will also need a Name.com account. The seller will then "push" that name to your account then the name is yours.
The person logs into their account, selects the name to be pushed, if with Godaddy selects "Account Change", enters your Godaddy ID & email then the name is pushed after the new owner accepts the push. With other companies like Enom, person just selects the name & enters your Username & the name is automatically pushed to your account.