When estimating, it is important to keep in mind the general rule of thumb. This guideline will help you to come up with a reasonable estimate that is likely to be accurate. By following this rule, by csiestimation you can minimize the chances of making an inaccurate estimate and wasting time and resources.

Your estimate should reflect the total effort involved. Notice that this is more than just adding up the individual tasks and recording their estimates. It is also more than creating a Gantt chart and applying numbers to task durations on it.

This will only give you an overly simplified estimate. Your team cannot work at its maximum capacity 100% of the time. There will be times when all team members are busy with other tasks or cannot work due to unexpected events, illness or vacations.

When creating your estimate, you should keep the total effort in mind and not individual task durations. You can then create the estimation for each task by using this guideline: 30% of the total estimated effort.

This is a general rule of thumb and not a strict guideline. Your estimation should be more accurate if you can provide a percentage for each task in your Gantt chart, but it is also possible to make an estimate using this rule.