Add some flavor. When cooking vegetables, it usually takes just a little bit of flavor to make them more appetizing. I'm not a fan of plain vegetables either. I don't think many people are. But you can add flavor (and nutrition) to raw veggies with healthy dips like hummus (great with carrots, celery, sliced peppers, cucumbers and more) or your favorite salad dressing (yep, it works for things other than salads). When cooking vegetables, most taste great with just a little salt, pepper and garlic. But I find that sautéed onions and garlic make just about anything taste good, so I often cook those first and then add some vegetables to the mix, which brings me to my next point.
Learn how to cook! I've had to teach myself how to cook as an adult. I come from a family of…whatever word exists to describe the opposite of a chef. Cooking has become quite a hobby for me and it's surprisingly fun, relaxing, entertaining and interesting. So how'd I learn to cook? Mostly by trial and error. But I can't take all the credit. I read books and magazines and would call my cooking friends to ask how to prepare a random vegetable that I bought at the store. Little by little, you'll pick up knowledge and learn how to make food taste (and look) great. Even if it doesn't come out perfectly, you'll still learn what NOT to do, and that's a step in the right direction.
Try, try again. Most of you are probably parents who have to deal with picky eaters on a regular basis. What most feeding experts will tell you is that a child has to try a food several different times before they might being to like it. What's true for kids is the same for adults. There are foods that I swear I hated my entire life that now, I really like. I just kept trying them in new ways, in different combinations, etc. I used to think I hated strawberries because I had never had a strawberry that I ever liked. But a couple years ago, I was on a mission to find that perfect strawberry, because I just knew I'd like it if I just found a good one. And what do you know--I did. And in the process I learned that, to me, organic tastes best. And so does freshly picked berries in summer (when they're at the peak of freshness and flavor), so I only eat them then. I also learned what color they should be to taste perfect. This is just one example of how you can't write off a food, especially if it's been a very long time since you last tried it.