Summarize:

Figure out how much you can reasonably afford to spend on a gift for your boyfriend. Be strict about it and don't get anything that goes over it. Contrary to what you may think, the monetary value of a gift doesn't have a huge impact on how much the recipient enjoys it. In fact, recipients enjoy cheap gifts just as much as they do expensive ones, as long as they're both thoughtful. Consider how long you've been dating. If you've been dating for six months or less, don't get him something expensive, even if you can easily afford it. You don't know how long the relationship will last. If you end up together for a long time, you'll have plenty more birthdays you can spoil him on. You may be able to get more bang for your buck if you buy something refurbished or hunt for sales. This is an especially good idea if you're thinking about getting him electronics. Most of the time they come with a warranty, and your boyfriend probably won't care or notice that someone used it for a little bit before he did. If you don't know a whole lot about what your boyfriend spends his time doing, then it's time to do a little research. You can learn pretty much anything on the internet in an hour. Spend some time searching his hobbies and interests and reading anything that talks about them. Read any websites dedicated to bringing hobbyists and enthusiasts together and see what's new in the field. You may need to take his level of experience and expertise when you're thinking of gifts. If your boyfriend has been skateboarding since he could walk, it doesn't make sense to get a beginner's board that he'll probably hate riding. At the same time, an expensive fly-fishing rod doesn't make sense if he's only gone fishing two or three times in his life. Ask people with similar interests for help if you're stuck. There are online communities for pretty much any pastime imaginable. Look for forums and other groups dedicated to discussing something your boyfriend likes to do. Make an account and explain your predicament. Chances are, the members will offer helpful advice that will guide you towards getting your boyfriend something he'll love. You may find lists that say something like "10 Great Gifts for Guys Who Love Hiking." These can be helpful, but sometimes they are just a marketing tool to sell stuff. If you get an idea from a list like this, try to find some actual reviews to see if it's worth it or not. As long as your gift fits into one of these categories he'll appreciate it. It shouldn't just be another addition to his collection of stuff. It should be something he will actually use or something that he can look at and remember all the happy moments you've shared together. Don't limit yourself to products. Sometimes experiences can make a much better gift. Make a video of all his friends and family sharing their favorite memory of your boyfriend. Schedule an activity that you know he'll enjoy that you can do together. He may not be able to show it off like he'd be able to with other presents, but it will mean a lot more to him. Stay away from classically bad gifts. It can be tempting to get your boyfriend something like a tie or shaving kit for their birthday. It makes sense, these are pretty common and obvious answers to the question of what makes a good gift for a boyfriend. In reality, these gifts pretty much always fall flat. If it seems like a stereotypical gift from a girlfriend, consider other options unless you're positive he'll love it. Lots of people make the mistake of getting one big gift and a bunch of small ones for their loved ones. It's easy to see why. After all, isn't more always better? In fact, giving small presents alongside your large one will make the main gift seem less special. It is better to put a lot of effort into one gift rather than no effort into multiple gifts.
Set a budget. Do some research on his hobbies and interests. Think of some gifts that are either sentimental or practical. Narrow it down to one idea.