I have had a Garmin 750 plotter for about 12 months now but I am not using it properly. When I just used paper charts I would plot the course to steer etc taking account of hourly tidal streams in the traditional fashion and mostly that was OK. I am having difficulty combining the plotter use of waypoints and the effect of tidal streams i.e. the track indicated on the plotter is OK but steering this track requires continuous adjustment of the boat heading to take account of the varying effects of tidal streams and is not an effective course to steer overall (I think). Reading the Garmin manual does not give any clue to this so how should this be done. How should I be doing this?