When we got our first house, we did our own tiling. OH tiled, I grouted - so we each learned half of the job. We got a decent cutter rather than just a nibblers. OH is pretty handy anyway, but mostly selftaught.
On the grouting side, I got a proper spongy grouting pad and I used to use old ice-lolly sticks to get a nice smooth finish (I later learned that wearing rubber gloves and just running a finer over also does a neat job). Wipe off the excess while still soft, and dust over the tiles at least that day to get any remaining residue off before it gets "stuck" (it's still nice and powdery for a few hours).
The most important thing we learned was to do it slowly - measure twice and cut once. Only mix as much cement/grout as you need at a go (if you don't buy premixed - much easier to get premixed though, if you have the budget). Mix in small batches even if have time to do a lot, can make more and it will allow time for a break.
Can look as good, if not better, than professionals if you take your time, use the right tools etc, as you will have pride in your workin your home. (not like some of the "pros" out there - there are good ones, but they are so busy and expensive).