Two things from experience. Buy, make, or have made, a long-handled tool. Make it long enough to work standing up. A piece of bent flat stock to engage the rectangular tab of the typical street valve welded onto a length of rebar and a cross-piece of rebar for leverage is usually all you need. I could list sizes but your better fitting it to your situation and some things, like the thickness of the rebar upright, will depend on length. Half-inch rebar works for short handled ones, maybe up to three foot, but 5/8" is less likely to flex.

Also the street valve may have remained unused for decades. Any valve that goes unused for that long can seize open, or closed, or break off entirely. It may need to be replaced the first time you try to operate it. So make that attempt early in the day and on a weekday when a plumber won't cost you an arm and a leg. Check with the water utility to find out who owns the valve. Most are after the meter and are the home owners responsibility. But some utilities see it differently and give you a break.

The good news is that if you inspect and operate the valve once a year it will stay good for a very long time. Checking the water main valve once a year and it is also a perfect time to check the main gas valve for function and to make sure you know how to turn off the electricity.

Working all the circuit breakers once a year, called exercising, can increase their reliability when they should trip. If you do your own electrical work this would be a good time to check all the connections in the panel for firmness and heat. But only do it if you know what your doing. Even then be careful.