Brainstorm for ideas. Try this brainstorming exercise to come up with money-making ideas. Take a topic that interests you. See how many different kinds of jobs or income producing activities you can find related to it. One of them is likely to be something that is practical for you to do.
This exercise is also a good way to find supplemental forms of income, two or more things that complement each other. Some, you can do simultaneously. Others, you might do consecutively, perhaps one during the summer and the other during the winter.
Think of a topic -- perhaps a hobby, something you enjoy doing around your home or shop, an activity you'd like to do more often, or something that you are good at doing. Start tossing out ideas of ways to make money that are somehow related to your topic. It's okay if they are far-fetched. It's okay if you don't currently have the skills, training, or knowledge to do them. It's okay if you can't imagine that anyone would actually pay you to do them. Just brainstorm ideas -- write them down without making judgments against them.
An example is fishing.
• Teach fly fishing.
• Make fishing videos.
• Work professional fishing tournaments.
• Work in a bait and tackle shop.
• Write and sell fishing articles to magazines.
• Work at a retailer, such as Cabella's, in the fishing department.
• Tie and sell flies.
• Teach reel repair.
• Teach rod building.
• Work as a deckhand on a fishing charter.
• Work as an interpreter on a boat tour.
• Teach outboard engine repair.
• Be a boat captain.
• Work for a commercial fisherman.
• Be a river fishing guide.
• Be a deep water fishing guide.
• Clean fish.
• Work in a seafood restaurant.
• Work in a shop that sells fish and seafood.
• Sew fishing vests.
• Assemble emergency kits to have on boats.
• Do boat repair.
• Mold and sell (wholesale or retail) lead weights.
• Write and sell cookbooks with fish recipes.
• Work as a taxidermist or assist one.
• Make fish related art to sell.
• Work for a fishing magazine.
• Paint pictures of fish.
• Do fish photography.
• Work at a fishing camp.
• Work at a fish hatchery.
• Work for the state fish and game department.
• Breed new varieties of fish.
• Represent a fishing organization at trade shows.
• Sell fishing equipment at flea markets.
Sure, some of these are a stretch. Some, you need special training and experience to do. But, by brainstorming a list, you get ideas. You start thinking about options. I'm guessing that right now, you are thinking about jobs related to fishing that I don't have on the list. I hope so -- that means you have the knack for how to brainstorm ideas on a topic that interests you. Give it a try!