Circling can be quite confusing unless its a sunny day - it's easy to lose track of where north (or south etc.) are. Before you start circling identify a landmark and note each time it passes through your field of vision. Remember that while you are circling your compass will not give a true heading.
To arrive safely you should be following a hand-rail of landmarks, and aiming off can be a very useful technique. Identify them beforehand and tick off against your intended track. Work out when each one should appear, work from the ground to the chart.
Agree absolutely about using Google Earth before hand. I also fine streetmap.co.uk is useful as well - you can get the 1:25k view which includes field boundaries.
In my view the more navigation you do including car, foot & marine all improve your skills and ability to not get lost.
And if you become unsure of your position don't press on until you have become sure again.