Howdy -- you can easily just mark your preferred densities on your template with a marker.Ventilation is indeed the hair-direction, but is irrelevant on a free-style system, as you simply `train`the hair into your preferred style by brushing and general grooming....once you are happy with it, simply apply knot-sealer to the underside of the base and that will `lock`the hair into place--usually after a few days wear and possibly the first wash [and vitally, helps prevent hair shedding from your base ] Freestyle is probably the easiest to work with for a new wearer overall . Hair sample ..about an inch long and the diameter of a pencil. What density you should choose will be determined by your own remaining hair --can you post a pic here so we can see what you have `to work with`? If not, send in a few pics to John with your order and he`ll have a good idea of what you should have . I think it`s a good idea for any potential wearer, or even an existing one thinking of changing their style, to `lift`a few pics from either a magazine or a website, showing the style you`d like to achieve [there are some good ones specifically showing men`s hairstyles] and submit them with your order ----along with pics of your own remaining hair, and John will cast his experienced eye over them and know what to order from the factory ... it can be a bit of a worry and a bit daunting for many who are not too sure of what to specify. Matching the density of the system to your growing hair is important. If you can post a pic or two here, I`m sure you`ll get a few helpful opinions anyway ..regards for now, Paul.