I like to use recipes when baking (for proportions, as stated by many others), but also change things up as wanted/needed. (For instance, I often use applesauce or yogurt in place of much of the fat; I also add a crapload of cinnamon to sweet baked goods. I’ll add stuff, too, if I need to use it up—small amounts of dried fruit, fresh fruit [not citrus!], etc, goes well in baked goods.)
When I’m cooking—like dinner—then I tend to not follow a recipe. Soup is easy enough to do without looking at a recipe (unless you have a specific goal in mind); greens are easy to saute in oil with salt and garlic. I tend to pick things that sound good and stay away from others.
For instance, tonight, I’m going to throw together some winter soup. I’m going to saute some italian sausage with onion, then add it to a crockpot with chicken broth, chopped carrots, the rest of the onions, whatever greens I have (mustard, collard, spinach), and some chopped potatoes. Spices, too—garlic salt, dry mustard, maybe some marmite for that yeasty flavor. Let it cook on high for a few hours—delicious.