Depends on their personality, managing their expectations is key. Also realizing you can have a good position and lose money, and thats a good loss. Proper position sizing and risk management will be the toughest to master.
there's a whole slew of interesting articles here http://www.trading-lab.com/forums/trading_articles-f61.html
Dont listen to naysayers, failed people will always try and convince you that you will ultimately fail too. Learn TA in a way that allows you to see consistent repeatable patterns and exploit them whenever they come up.
remove all pressures to make money 1) paying rent, 2) food Focus on executing right trades, with no emotions each and every time. Try not to be excited when you win Cut losses faster then you can get depressed when you lose. Always think contratian, when you are winning $$$, step away from the sheeps and sell. Focus on where the big players execute their trades. Good luck for the next 3 years.