You do not need to set the timer or need to watch the clock to boil eggs. Boiling eggs is easy. Here are simple techniques that I use to know when an egg is done.
The size of the vessel should depend on the number of eggs you need to boil. The vessel shouldn't be too big if you are boiling just 1-2 eggs.
Place the egg in the saucepan and pour enough water to cover it. The egg should be fully immersed in the water and the level of water should be roughly 5mm above the egg. You can add a 1/2 tsp of vinegar to the water at this juncture, as this prevents the eggs from cracking. The egg is good to use only if it remains sunk, if the egg floats, it needs to be thrown away, as it would be rotten. An egg that stands in the water, instead of lying on its sides would not be very fresh.
Light the flame and set it on medium and place the saucepan on it to boil, The water will begin to boil within a couple of minutes. You can reduce the heat at this point, but ensure that the water continues to bubble.
As time passes the calcium from the egg shells will dissolve in the water and you'll find the water become cloudy and the sides of the vessel forming a distinct watermark, from the calcium in the water. The water level will also reduce.
There are two ways to know that the eggs are done –
1. The eggs would be done when the water evaporates and the gap between the watermark in the vessel and the level of the water is about 3/4".
2. The next way of telling that the eggs are done is by observing how much of the egg is submerged in the water. If the portion of the egg outside the water is approximately 1 ½" diameter the eggs would be boiled.
"A love affair with knowledge will never end in heartbreak." -Michael Garrett Marino