What is a decent amount of Bitcoin you should have to make day trading worth while?
Since it is obvious that you are just a newbie in the field of Trading, it would be better if you play it out first with an amount that you can afford to lose. Like for example, 0.05
BTC is not that bad for starting day trading. You have enough to cover up the fees and you get a good chance to experience day trading first hand and when you feel like you learn the know-hows then add more to your initial amount for trading.
He is just newbie so my question is he will handle day trading pressure? Will he survive in day trading? I think it is not easy he needs to learn many things in trading because trading experts also failed in the day trading. and 0.05 BTC is not a small amount at present price. if he is ready to take the challenge and he can do it means no problem.