After launching the Cash App Investing platform in 2019, many of the 36 million Cash App users have dabbled in the stock trading feature. Even Megan Thee Stallion recently gave away $1 million in stock through Cash App as a high-profile partnership with Jack Dorsey.After you buy stocks on Cash App, how do you go about selling them? Here's the skinny on selling stocks you hold in your Cash App account.Look at your portfolio to find stocks to sellIn order to sell a stock on Cash App, you need to first own it in your Cash App portfolio. To find your portfolio, open your app. Once you're on the home screen, scroll down until you see "My Portfolio."Your portfolio is the collection of stocks you own that are held on that specific platform. You might have other investments elsewhere (like a 401K, for example), but this is where your Cash App investments live.Make sure that the stock you want to sell is in your portfolio before proceeding.Click on the stock you want to sellAfter you decide which stock to sell in your portfolio, click the company's ticker. You'll be directed to a page that shows a "Sell" button.Click to sell and specify how much stock you want to sell. In Cash App, you can do this with a dollar or share value since the platform offers fractional investing. The platform gives you the opportunity to choose a preset or a custom amount in the sale.Cash App protects your investment, so expect to put in your PINWhen you're ready to finalize the sale, Cash App will request that you enter your PIN or Touch ID, depending on your account settings. This is an added layer of insurance for your investment, to protect you from fraud or theft.Where does your money go after you sell a stock on Cash App?Once the sale is executed, the funds land in your Cash App balance. This process could occur on the same day or take as long as two business days to complete.Be aware of trading limits on Cash AppIf you sell a stock outside of market hours (9:30 a.m. to 4:00 p.m. ET on weekends, excluding federal holidays), the trade won't execute immediately. It will go through once the market opens.Like most brokerages, Cash App also maintains day trading limits. Cash App says, "When you buy stock using Cash App Investing, you are limited to the buying power of your Cash App balance and your Add Cash limits. You’re also limited to three day trades within a rolling five day trading period. A day trade is considered buying and selling the same stock on the same trading day."If you break these rules, your ability to day trade could be suspended or terminated.Don't forget about capital gains taxesShort-term and long-term capital gains taxes come with the investing territory. If you're seeing great returns, don't forget to put some of those funds away for tax season. Trades held for less than a year incur higher tax rates. Capital losses can be written off up to $3,000 per individual.