You can monitor your crypto portfolio and sell your cryptocurrencies by using various tools and resources that allow you to track the price movements of cryptocurrencies and the market conditions that affect their value. Use charts, indicators, news, forums, podcasts, etc. to analyze the market trends and opportunities. You can also use various strategies to maximize your returns, such as dollar-cost averaging, diversification, risk management, and trading signals. You can also use social trading features, such as eToro's CopyTrader and CopyPortfolios, to follow or copy the trades of other successful investors or join communities of like-minded traders. When you want to sell your cryptocurrencies, you can do so by following a similar process as buying them. You will need to enter the amount of GBP or BTC that you want to sell and click on the "Sell" button.