If you’ve followed the posts so far you are well on the way to creating your project plan. You have a list of tasks needed to deliver the outcomes of your project. You put your tasks into logical groupings. Then you arranged your tasks in a logical order to show which tasks must be completed before others can begin.
Now you need to estimate how long each of those tasks will take. At this stage it is only an estimate – you can’t know for sure how long something will take unless you can foresee the future. You won’t know, for example, what problems might slow you down, or what you will have to do to fix these problems. Estimation can also be difficult if you are doing work that you have not done before, so you have no experience to base your estimate on. Estimation can also be difficult if you are doing creative work, such as design – who knows how long it will take to create a design that you or your client is comfortable with? You might also need to know who is going to do the work – someone with experience will work faster, and make less errors, than someone without experience.
In short, estimation is fraught with difficulties. No wonder then that this can cause problems with projects. Under-estimates can mean the project team is working against difficult or impossible targets. It can mean that your project is under-funded – for example if you asked for costs to cover 100 days, but should have asked for 200 days. Impossible timeframes and lack of funds will cause stress both for you and your team.
So, what can you do to improve your estimating?
For now, while we work through the first version of your first project plan I suggest you keep it simple.
Think about your first task, and work out how long you think it would take you. You need to consider how much time you are devoting to your project. Let’s say you are building a fence. If you think this would take you five days to build, but you can only do this at weekends, then it is going to take you two and a half weekends. That’s three weeks – not one.
Use your experience. If you have built fences before you will have a better understanding of the effort and problems involved. Compare the fence you are building now to the fences you have built before. What is the same, what is different? What does that mean for your estimate?
Use the work breakdown structure to visualise each task. A ‘dry run’ of your project may help you to estimate. How long will it take to dig post holes? How long will it take to procure and transport the timber? How long will it take to set the posts?
When will you be finished? This is about being clear on the scope of your project. Are you finished when the fence is built? Or when it is painted or treated? Or when you have painted a second coat? If you are not completely clear on scope your estimate will be way out – and it could be that your project expenses are way out too. If you underestimate cost, you can lose profit.
Now, you have ordered and grouped tasks, and you have estimates. All you need to do now is build your plan.
