A very common issue for many fly tiers is the heads of their flies are either too big (as in bulk or length behind the hook eye) or simply not that neat and clean. Maybe there are loose thread wraps poking up between other thread wraps or too many threads wraps are applied in an attempt to control the whole mess. Nice neat and smooth heads can easily be formed if you remember to start the finished head at the eye of the hook.
Often the head of the fly is created to cover up butts end or clipped ends of materials that we have used in the creation of the fly (Figure 1). Most tiers will begin forming the head of the fly by applying wraps of thread on the materials ends and advancing the wraps forward. The problem with this is the thread invariably slips off the abrupt end of the material and we then try to continue to wrap thread while "climbing" back up onto the materials. This will always end in a larger and sloppier head than we want.
Instead, once all of your materials are bound in and you are ready to make the head and cover up the material ends, reach your thread up to behind the hook eye and start applying thread wraps away from the eye of the hook to form the head and cover-up any remaining materials (figure 2 & 3). This will help create a taper up to the materials as you are forming the head and thus have more control on your thread placement and the shape and size of the resulting head.
Try this simple technique to create smaller, neater and cleaner heads on your flies.