If it's just a two-laner, I migrate carefully to the center portion of the lane signaling appropriately.

If there's a left turn lane, I position myself into the center of that lane ever so carefully.

If it's too difficult, I sometimes will try the "fake right turn", i.e. turn right, but make a counter-clockwise turn left to be headed the direction I wanted to go. This is also a good evasive maneuver if a car from the right doesn't appear to be seeing you.

All of my techniques come from a book called
The Art of Urban Cycling. It's a handy resource.