Force yourself to build a few projects from start to finish with only hand tools. You'll need:
* a reasonable set of bench planes (jack, try or jointer, smoother)
* a decent dovetail saw
* a good-cutting 5 1/2 or 6 point rip saw and a common crosscut saw (or if you're lucky, 11 or 12 point carpenter saw in crosscut)
The easiest way to get comfortable with tools is to mark out your expectations and then learn to hit them with tools. Time spent ripping a board will make you a better sawyer sawing a tenon. It's not direct, but it builds your senses in seeing square, feeling what's going on in the cut, etc. Time spent try planing will make you better at it - you'll learn skills like we had an argument about on here before, which was the assumption that you would always plane the ends off of a flat board or a jointed edge if you cut the full length of the board - I never do that. I generally plane the wood slightly more hollow over the coarse of flattening - with through cuts. It's intuitive - i didn't learn it as a party trick, I learned to do it because it's faster - I can just plane to a mark and that's it. Laziness makes us better at some things if we allow it to.
If you do entire projects by hand, you'll learn where you need to cut shy of a line and clean it up, etc, a lot faster than guessing at it and taking someone else's advice. Set your expectation for your accuracy, results, and meet it. If you come up short, adjust. It really takes very little time if you're doing everything by hand, and you get a level of comfort that is really nice. You also learn where the accuracy you're looking for really counts, and where you can skirt it. I don't mean doing sloppy work by that, but things like a table leg - if it's M&T on two sides and they need to be square, they need to be square, but perhaps outside of those two sides, the rest needs to be square *to the eye*, which is a slightly lower standard.
The other option is to be very regimented on the little bit of hand work you do if you're busy making thing like cut lists, project plans, etc, and shuffling work around from machine to machine. It's less interesting to work that way, and you never feel like you can relax until you've really done a lot. And you'll never get quick with planing that way. The speed you gain planing if you work an entire project by hand a few times will carry over later if you decide to do all of your rough work with machines, and you won't find yourself doing things like table sawing a board, then planing the marks off and finding out that you planed the board into an out of square shape.
Lastly, check your ego at the door and give yourself permission to make and fix mistakes. You'll learn from them, and you'll learn what's not terminal and what is. Ultimately, you'll have less scrap in later projects. It's extremely uncommon for me to waste anything now (be it metal on an infill plane from a mistake, or wood on a cabinet, etc), but I constantly misread something from plans and made a set of rails a quarter inch too narrow when I was working with power tools only.