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A couple of people, particularly those who haven't navigated before have asked me what the one-in-sixty rule is that I keep referring to in my posts. So, here is an explaination. The one in sixty rule is a method of navigation to get you back on track. The philosophy is that, for every 1 mile off course you are in sixty miles, you are 1 degree off track. When you work out a heading, you adjust for the wind. However, often, the wind is different once you actually fly the leg.
Hence, at a designated point, about half way along the leg, you determine how far you are off course (eg. if I was going to fly over a lake, but the lake is 3 miles to the left, then I am three miles off course).
You then work out how far you have come, for example 20 miles. If you are three miles off in 20, then you are going to be 9 miles in 60. This means that you are 9 degrees off course. If you adjusted your heading 9 degrees to the left, you would fly parallel to your original track.
You then take this one step further and work out how long you have left, for example 30 miles. 3 in 30 is 6 in 60, so you add 6 degrees to the original 9, and this will put you on a course to intercept your destination. It has worked everytime that I have done in properly and I wouldn't fly without using it now, unless I am track crawling (flying from landmark to landmark).
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I have to admit, I've never done one in flight, my instructor just taught me to note if I was drifting off track or not and just add/remove a bit of wind correction. While I guess I'm quietly noting whether I'm on track or not throughout the rest of the leg and adjusting for it, I have found its better than flying off track for half the leg, then trying the other half to correct the mistake. (I do of course know how to do them, the CPL nav exam is a 1:60 exam...)
Another handy tip that was taught to me when I was doing MECIR (though its for VFR) was how to do a complete flight plan with only a map...and a pencil. No wizwheel, calculator, ruler, protractor, just map and pencil. Simple as it sounds, it does work....you can guesstimate a heading within maybe 5 degrees (and pick up the error once in flight), you can use some rules of thumb for wind correction and groundspeed, should come quite close to measuring the distance for the leg accurately within maybe 5nm (depending on the chart) and come within about 2 mins of what the ETI should be.