I'm at severe risk of getting flamed here, by some of the 'experts' but here goes..
"climb FL230, cross DKB at FL200 or above", This sentance means for the pilot to increase altitude to 23,000ft (FL230), and to make sure that he crosses DKB, which I believe is a VORTAC, at at least 20,000ft or more (given his assigned altitude he has to make sure he is between 20,000ft and 23,000ft when he crosses the DKB VOR).
"turn right heading 150", now this is where I am at risk of getting flamed. Translate this as make a right turn, to 150 degree's (although I keep thinking that its turn 150 degree's to the right, hehehe
"Turn left by 20 degree's and report that new heading", now this probably backs up the last sentance, the pilot is most likely heading 150 degrees (roughly SSE) and the ATC would like him to turn left 20 degrees (which SHOULD be 130 degrees, which is almost exactly South East), and then contact ATCO to tell them their exact heading, which should be 130 degree's or thereabouts.
"maintain present heading", uhhh... keep heading in the same direction as you are currently flying
Did I screw up? Are all you experts mad at me?