For short term trading or day trading - IMO stops are a must!
I have been starting to avoid stocks below 2c as the gap between each pip is too great (over 5%), its great if you make a few pips but not if things head the wrong way can be a sizable loss.
For other stocks above 2c, 5c, 10c etc for a short term trade or investment - I generally will place a stop at a support level using the charts and if im still keen on the stock from an FA side I can generally I can buy it lower after it breaks support. Remember the trend is your friend
For Day trades my stops are generally within 2 pips
The key to trading - Tight stops and let your winners run till the chart tells you to sell!
Even if you only get 50% right you should be making good profits
As I did with POK today at 22c