I recommend starting trading with a capital of 0.001 BTC. of course, with sufficient capital will get a lot of results too. But you also need to be careful in trading and always make your trading plan in order to minimize losses and maximize profits.
It's a good start with your 0.001 bitcoin but when your going to trade make sure that you have enough money to start or you can have some loan if you have a stable job where you can get money. To be honest you can't avoid loses the bigger you trade the bigger the profits of course opposite of losing too , If his going to trade now it will always depends on his profit target make sure to do a good research before risking his money but it always depends on the price on the market if you can see the dept in the market then good for him but everything you wanna learn about trading you can look em on internet join in groups watch youtube there are several good tutorials where i learned so much also you can learn from your mistake too just don't do what other's says follow your own gut.