A torsion spring holds real stored energy, enough to snap a socket wrench out of your hand or worse. We're not going to pretend there's a safe shortcut here - winding or unwinding a torsion spring without the right bars and a locked-down door is one of the more dangerous DIY jobs in the house, and it's the single thing we tell homeowners flat out not to attempt themselves.
There are smaller things worth doing on your own. You can look at the spring and tell us what you see before we come out - a visible gap in the coil, a spring that's stretched longer than its pair, or one side sagging lower than the other. That kind of detail helps us bring the right spring size on the first trip instead of a second one. Beyond that, the honest limit is: if the door won't budge, or it's slammed down and won't lift, leave it closed and call. Forcing an opener to fight a broken spring burns out the motor, and that's a second repair stacked on the first.