When you first bought your home you probably invested in a standard six sided socket wrench set. The most common nut around the house is the six sided (hex) nut that you find everywhere in your house. Products you bought and have had to assemble have also had the hex nut so you've gotten a lot out of your socket set. After you've been in your home for a few years you have most likely bought appliances with small engines. You may have a lawn mower, gas weed trimmer, tiller, small gas chain saw, maybe a snow blower. IF you're like most people you'd like to save some money by doing some maintenance and minor repairs on those small engines yourself. You've check owner's manual on the internet and gotten direction on how to change filters or adjust carburetors and throttles. It really is something you can handle. You'll need to follow directions and take notes on how to reassemble the small engine but a lot of this you really can do yourself.
Now you've decide to start tackling that small engine repair. The socket set you've got will be very useful along with stander flat head and Phillips head screwdrivers. But you'll find you need to get into to some hard to reach areas, and also you start seeing nuts and screws that you're not familiar with at all. What do you do now? Simple, go to your local hardware store and tell them what you've run into. Sketches are good to take along with you when you go, and with your description of the screw head or funky nut you've found the hardware people will be able to help you with just about anything you've encountered. They'll take you over to screw drivers, wrenches, and the socket wrench sets to help you find what you need. But you don't need to buy entire sets of hand drivers and screw drivers. There are a number of screw bit, and sockets that you can use with the ratchet wrench in the socket set you already own.
These accessories to a socket set are a great way to go and more economical in the long run. You can get low profile flat head and Phillips screw driver bits, along with bits for screws you're not familiar with. Same thing with any different kind of nuts you run into, you'll find sockets that will fit your socket set's ratchet. You may also need extenders of varying length to get into those hard to reach areas. You'll be surprised at how they put that engine together and may need deep well sockets not standard in most socket sets to get at some nuts or screws. Don't forget to buy spark plug sockets for your socket set. They usually come in sets of three, to change car and small engine spark plugs and should be all you need for any spark plug you run into.
You may want to buy the entire socket set or bit set they recommend so you have an array of sizes. But one or two sizes may be all you need, and you can just add them to the socket set you already have. Small engines are usually pretty simple so most people can work on them themselves instead of taking them to a professional, and having fixed it your self is a great feeling. Remember to wear eye protection and have a clean work bench, this will also make it a safer way to work.