The risk for selling a put is actually less than buying the shares as your break even is the strike MINUS credit collected....and the capital requirements are generally less. Also as you have already noticed it actually improves your over all profit if you take profits before expiration...thus freeing up the capital to re-establish another position. When selling options you not only become profitable if price moves in your favor but you also get ahead as time decays and/or volatility contracts. Selling options as close to 45 days to expiration when Implied Volatility is near or above 50% increases your chances of success. Puts can also be rolled into another expiration...especially useful if you are nearing expiration and the put is not yet profitable enough or being tested.
Only trade very liquid options with a lot of open interest. For starters if the bid/ask is more than a nickle wide...stay out. Also being short a put allows you to sell a call without any additional capital requirements...creating a "strangle"....this also adds to the credit received thus improving your break-even further.