Eight to ten strokes on each surface should be quite sufficient. The amount of time might seem excessive, but the rewards are great for your dental health. The answer is that, to be effective, one should floss each day. There are many flosses to choose from on the market. Each one works.
Personal preference is up to the patient.
Thickness, waxed or unwaxed, etc. are for the difficult spaces that exist in teeth. Flavored, non-flavored flosses are available, again it is personal preference of the patient. The main thing to remember is to floss on a regular basis to maintain good oral health. There are commercial devices that can aid one in overcoming these problems. Recently, a company has developed an electric motor type flossing device.