First thing I do is mark the board with a Sharpie where I want to break it, then I double-check it. I cut thru the holes, not between them.
To cut the board, I clamp it in a vise with the line where I want to break it just above the jaw. I use the vise as a guide for scoring both sides with a box cutter. After it's scored, I bend the board and it breaks. Next, I use a grinder to clean-up the cut edges and round the sharp corners a little.
After that, I mark where I want the strips cut and double-check it. Keep in mind that most views of a Vero board layout are from the top, but you need to mark & cut the bottom side. That means the pattern is mirrored. I used to use a 1/8" drill in a pin vise, but that took the better part of a minute to cut one spot. These days I use a drill press. I have the stop set so it drills about 1/2 thru the board. Perfect cuts and I can make 20 cuts in the time it took me to do one by hand. I should heed Feral's advice and use protection for eyes & nose.
Inspect all of the cuts under magnification because one tiny sliver of copper will turn a build session into a troubleshooting session.
Clean the copper with alcohol and you're ready to build!
I install jumpers first, then resistors. If you're socketing the ICs, then install the sockets
before the resistors. I do a few at a time and check it against the layout drawing before soldering. It's too easy to install a part one hole over. There's no solder mask on most Vero boards, so be careful to avoid making solder bridges between strips. Each part installed acts as a landmark for the next few parts. When the soldering is done, inspect everything to make sure parts are installed in the right holes and there are no solder shorts between strips. When your board is done right, it looks like this. BTW, this is a fiberglass board from Amazon.
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