I think the most common factor to control emotions in any type of trading is to pre plan the trade first and manage the trade as per plan only. Suppose you buy Bitcoin at $8K and take risk till the price $7500 and target your profit at $9k so whatever side is hit, you will always be prepared for it. Even if BTC crosses $10K it will not make you regret to be in trade as you had already meet the target. By planning a trade properly and execute it as per plan makes you a  professional trader.