HAnd tools get my last name engraved on them where you can see it.
Power tools also get inscribed but I want everybody to know they're marked so I spraypaint either my last name or initials with a stencil big and bold on them.
My clever mom taught me to 'etch' on wood (rulers, etc) and plastics (calculators, etc) by scratching my name into the object and using a Sharpie or similar permanent marker to write my name over it. The ink then penetrates the etched letters and can't be removed easily. This works for a lot of smaller items unless they're dark colors.
Read on this board about someone who painted his tools pink. Easy to spot, and as few men would want such tools with such an unmanly color, rarely get stolen.
Use a carbide vibe engraver and then go over it with a Sharpie.
Also, if the tool can be disassembled, I mark every piece of it (ie my Circular saw is engraved on the handle assembly, skid plate, blade guard, motor housing, and blade housing).
My former Fire Chief was a master carpenter, and he told me about getting tools stolen, and having them show up with old bodies (his) and new handles... minus his markings.