Spreading flakes evenly is probably one of the more challenging parts of the project. Very light density and very heavy density broadcasts aren't too tough to nail, but those in-between ones require you to pay attention.
Do practice your spreading! You can do this before hand by putting down a large piece of plastic, or practice after the primer coat is tack free.
There are several spreading techniques, some folks like the overhand throw, some like the chicken feed, others the toss up to the rafters. All work, you just need to practice each and see what feels best and results in an even broadcast.
But I think the most important tip is this... Use very small hand fulls of flakes! If the density is too light, it's real easy to toss out more flakes, however if the density is too heavy, well there's no way to un-ring that bell.
Some folks do like using the fertilizer spreaders, but even with one - practice.
Another thing I would strongly recommend for any floor over 300 ft2 +/-, spike shoes. They'll allow you to walk on the still wet coating and evenly spread those flakes.
Flakes are largely an aesthetic consideration, but they do have some practical functionality. A vast floor area of a solid color will show dirt and dust, even a light broadcast of flakes helps mask that debris so one doesn't feel compelled to constantly sweep up. Also if your original floor is less than perfect with gouges, bumps, cracks etc. that you can't or don't want to quite cover and smooth out, or if you really punish and abuse the coated floor, flakes do a great job of masking a host of sins.
