This may be a silly question - Ok so I now have £700 invested in bitcoin . Let's say it goes up by £50 - do I remove the profit and leave the working capital( £700 )in bitcoin ? Or do I take the lot?
If I take the lot then when I buy back in It may pay a higher price. What do you suggest?
This is exactly what trading experience will solve for you. I believe that everyone has questions like you but if you only guess about the trend, it is really a gambling game.
To be clear on this, you should really read about the trading documentation and there will be some tricks on resistance and support. It will help you a lot in making decisions.