Almost all projects I start now, I use a very similar approach — of course there are many best practices all of which have their merits, but for me, this simple method seems to work no matter the size of the project.
List your stakeholders
Who is the main sponsor of the project / problem you are trying to solve and who are the people and departments which will contribute to defining the tasks ahead, the solution options / design and ultimately its implementation.
Define the problem
It’s always good to have a sound problem statement from your stakeholders. Articulate the problem in the terms of your business. In financial services, I try to think about problems in the context of time, technologies, people, markets, profit/loss, cost, regulation and competitors.
Define key assumptions
List out assumptions for all stakeholders to agree to — it’s always interesting to see everyone’s assumptions and how they don’t know always match the consensus view. In my opinion this is so important when it comes to project initiation and scoping.
Make sure you think about assumptions in the context of the problem — think about the product, design, regulatory needs and the implementation timeline.
Evaluate your solution options and project viability
You should now have a good understanding of the what and the who. It’s now time to go deeper into developing and evaluating solution options and overall project viability.
Start with two or three options and create some basic cost / benefit analysis of implementing these solutions. Evaluate the probability of the project’s success in the context of costs & benefits and also the timeline you will need to have the work completed in. You should consider the impact to the current business, profit & loss, return on investment, environmental impact, social impact and risks to the organisation. Also consider whether the project will result in any on-going costs or burden to the existing business and staffing.
Ultimately you want to make a decision whether this project is worth the time and effort or not and if it is, how will you go about developing the design and implementation plan.