Japan's Seiko Watch Corporation makes Lorus watches. They are available in many styles, including sports models. While the wristbands vary, each is adjustable to give you a comfortable fit. The process needed to adjust them is the same. You will need a watchband link removal tool, which you can buy locally or online for £3 to £6.
Unclasp your watch band by lifting it and unsnapping it from its lock. Open the clasp entirely.
Find the spring bar, the small metal post on the clasp of your watchband. Using the pointed tip of the watchband link removal tool, push the spring bar through the clasp until it is free from the watch. At this point, the clasp will be loose and no longer attached to the watchband.
Grasp the clasp of the watch and hold it tightly, using your thumb and pointer finger. Slide the clasp off of your watch band.
Loosen the wrist strap by moving the clasp toward the end of the watch band. Move the it one link farther away from its original location and replace the spring bar. Move the clasp one link at a time until your watch band fits comfortable around your wrist.
Replace the spring bar by using the watchband link removal tool to push it back into place.
If you find that your wrist strap is still too tight, even after moving the clasp to the very last link, contact Lorus and order additional links. You'll need to know the make and model number of your watch.
Make sure the spring bar is fully inserted before trying to clasp the watch band. If not, the watchband may separate.