How to be a good trader

How to convert the internship: 

Generally, be keen (first in / last out, even if they say it's not necessary), ask a lot of questions (albeit once), make yourself useful (even if this means fetching coffees / lunches). Above all, show that you're engaged and actually thinking about the information you're being given. The most impressive interns I've seen have been those that have sat with a trader / PM, asked relevant questions, and then gone away and thought about the responses they've been given. They then come back later that day / later that week and ask extension questions. For example: "Hi X, on Monday we talked about options and how a positive gamma position adds to your EoD P&L when there's meaningful underlying delta movement - I've had a think and was wondering whether, because of the implied delta you're accruing on the up- and downside of these moves, this means in theory you could trade around that position and add further to your P&L?"

What makes a good trader in future: 

Broadly speaking, I think the "desirable" traders of the future will be versatile across asset classes, will be literate in statistics, and will be able to code. In terms of how to develop the "soft side" of your skillset into that of a successful trader, get your feet wet. You'll develop the mentality best by investing your own money (no matter how little) and learning to take your losses with your gains. The sooner you're comfortable taking a position with real money and not worrying about it too obsessively, the better. Then, when you go to interview, make sure you have a thesis behind your positions. I'd advise sticking with a supportable, evidence-backed narrative than quoting technicals (e.g. MACD, Fibb retracements, etc.) - I ding 95% of candidates that do this.