Though it occours to me that having a Clone/Doppelganger of myself may seem cool and would be in my view "highly intresting" at the time. However in the best interests of myself, the Clone/Doppelganger in question, would barely get past saying "Hey there! I am---" before I have taken the top of his head clean off with a 12 gauge shotgun.
Tests are pointless. If it Looks like you, get rid of it. If you want someone to do your work, hire Maids (Sexy French ones), like J. M. Pescado pointed out. If the clone is like you, then it's likely that said clone will turn down work and will give it back to you. Hence nothing would be done.
And as far as tips from the future go. Well apart from it making a paradox and then killing your future self, because your future has changed, therefore making it impossible for him to come back and tell you the said "life altering Tips" Therefore him not actually dying and your back to step one. Paradoxs, so much fun. Really, I need a diagram to show this kind of talk.
There can only be one of me. If said clone kills me first then this rule still applys.