One of the biggest complaints I hear, particularly from older tiers, is they can’t clearly see what they’re doing, especially on smaller flies. In many cases, not all, there are some easy solutions.
The first, is to go to the Dollar Store and fill a basket with reading glasses in a wide range of strengths, the lower numbers being less powerful than the higher.
Try on the different pairs to determine which provides the clearest view of a fly at a comfortable working distance from it. Take note of the magnification and either use them or get a better pair that’s the same strength. For me, I need even more magnification so I order glasses online. They’re not Dollar-Store-cheap, but they’re still reasonable.
Another option is a large magnifier placed between you and the fly. Some models even include a ring light to illuminate the fly, which makes seeing it a good bit easier.
Still another option, which may look a little goofy, is a headset with flip-down magnifiers. Once you get used to them, they function remarkably well, and this pair cost just $5, has built-in variable magnification as well as small lights on either side.
For some, seeing better is often the first step toward tying better.