I think that 3% per day is absolutely ridiculously unreasonable. I've been extremely successful since trading full time the last 3+ years (position trading, not daytrading), with several hundred % returns on my overall portfolio, but I'd hand all my capital over to you to manage if you could get me 3% per day.
Do you realize that if you had $1000 and made 3%/day for one year, you'd have over $1.6 million after that one year? Even at 1%/day you would multipy your money over 12 times in one year.
More likely, you'll have some 1% days, some 3% days, and quite a few -1% and -3% days as well, along with a bunch of 0's. The trick is limiting the down days and maximizing the upside days.
Good luck...
Aloha