So, here's the thing. Sometimes plans are necessary. The complexity of the project really can only be tackled by sitting down and creating a good plan. It's the only way to deal with all the moving parts.
Some others... Well, red team it. You go in, like you belong. You find the one thing that gives you access. You exploit that and you gain the needed foothold.
All you need is the right tools.
Right mindset + right tools + practice = Getting in.