Call your broker. Some like TD Ameritrade allow g

Call your broker. Some like TD Ameritrade allow gray trading and a limit order can simply be placed. You may need to wait a bit as buys and sales only go by matching lot sizes. Easier to buy/sell 100K shares then, say, 124,550 shares. If you have another broker, they may require you to call for each trade. A tad more annoying and time consuming, but necessary with some.