One option available to people is to have a stock trading account for your Roth IRA.  Simply pick and choose the stock you want to buy and put in your order much like you would do with a regular trading account.  I personally have a Roth IRA account with TD Ameritrade that does just this.  They also have a plethora of tools to find the stock that is right for you or you can go out and find some trading software out on the web.  It is entirely up to you which way you choose.  The beauty is that any gains realized in a Roth IRA are tax free and thus add a tax shelter of sorts if you are proficient in trading stocks.