Something that took me ages to get out of the habit of, is dragging the object you are moving with the mouse button held down - just click once to start moving and click again when (and if) you get the object to where you want it to go. Also holding down the up, left and right cursor keys when moving restricts movement to the blue, green and red axis respectively - I often have to make multiple moves bound to a couple of axis to get an object to where I want it using this method, but at least it's not so random as when the cursor is trying to snap to various geometry as Sketchup makes a best guess at where you are aiming for.

Another little trick I use alot is when rotating a grouped object and I can't get the ptrotractor in the right plane is to draw a quick cube next to the object to be rotated, select the group to be rotated, hover the prtractor over the cube face that corresponds to the plane of rotation then hold shift down and it will stick in that plane whilst you move the protractor back to the point of rotation on the group to be rotated, then do as normal.

Oh if you haven't already found them get the Cleanup Tools addon for Sketchup - its somwhat aimed at games 3d modelling, but is useful for automatically tidying up reversed faces, co-planar faces, orphaned line vectors/edges etc http://forums.sketchucation.com/viewtopic.php?t=22920

Hope that helps and isn't teaching to suck eggs..


Chris