I hunt only with vintage sxs guns. All have double triggers. It's pretty simple and doesn't take long to learn.

Don't try choosing which barrel to shoot: start with the forward trigger (right barrel). This is usually the most open choke. You just slide your finger to the second trigger for a second shot.

Get to a trap range and shoot a few rounds( of trap) from low position so you learn to mount the gun while you disengage the safety.

Then practice shooting doubles at trap, also from low position. This helps develop muscle memory to move on to the second trigger.

Don't overthink this.

The biggest problem I've seen folks have in the field is trying to pick a choke for a shot: slows them up, often they can't find the second trigger for a follow up to the usually missed first shot.

I'm sure others have better ideas and advice.