Ready to part with a stock in your portfolio? Here's the step-by-step guide for how to sell stock, including how to navigate order types, fill in a trade ticket and choose an order expiration. Assuming that you bought your stock through a financial advisor, either in person or on the phone, you can also sell your stock this way. Financial advisors will typically execute a sell order within 24 hours. Note that, in this case, you must either speak directly to your broker or put your request in writing. But this time, you enter a stop market order for $45. And again, you wake up to find the stock plunged instantly to $25. This time, though, all your stock would have been sold. But, your online broker will sell the shares at whatever the price was the moment your order converted to a market order, which in this case could have been $25.