Cutting Drywall isn’t all that difficult, and we’ve talked about it in the past few posts. Because you never know what’s behind a wall (even with a good stud-finder that can detect metal and A/C current), you should always cut very carefully and not just recklessly start sawing without knowing for sure what’s in there.
A trick I often use when cutting larger holes is to not do it all at once, but start with a small square hole and expand outwards. You don’t want to go too deep with the jab saw on your first small hole to avoid any obstacles inside the wall. Once you’ve got that out, put a finger in there to feel if there’s anything behind there. Expand the hole until you can fit a few fingers and reach a little further, then keep going until you can reach all the way in. You can choose which sides to expand the hole based on what you feel behind there. For example, if you feel the stud an inch from the left side, you can expand the hole further to the right to keep your hole in the proper cavity.
Here’s an example of the progressive cuts I made in a recent project:
The only problem with this approach, aside from taking a little longer, is that you can’t re-use the section of drywall you just cut out. But, in practice, that’s usually not possible anyway since removing the drywall attached to studs (usually glued or nailed on) is a destructive process so you’d need a fresh sheet anyway.