There won't be any one single answer to this, although there seem to be those that think there is. They may be right, but my gut says "nope". Here are some opening thoughts.
I) General Goals for Life During the Development Process
The approach you choose must allow you to fulfill the following goals:
- ALWAYS have something to demo to stakeholders
- ALWAYS have the next thing "cooking" as well
- ALWAYS be able to answer stakeholder questions regarding approximately when they'll be able to see a demo of such and such a feature.
- ALWAYS be able to be flexible should stakeholders require
you to change the implementation sequence.
- Be able to distribute work should the opportunity arise.
II) Create a Team Environment at the outset
Even though you are the sole developer right now, be certain to set everything up as if there will be an entire team working on your project. It's surprising how fast we tend to lose the basic disciplines when working alone - always work as if you're part of a team, even if the other members are "virtual".
There are some design and implementation decisions you'll want to make first.
III) Feature Set Sequence
Do you intend to present the product whole and complete on the first "live" release, as opposed to doing it iteratively? If iteratively, you'll want to determine the feature set that comprises the minimum viable product (MVP). Then you'll want to set up (or suggest to stakeholders) the feature increments (milestones) for the first few cycles. Once that's done, you'll have a schedule, and be able to fall into a design/develop/test/release cadence that delivers expected results in the expected timeframe. That cadence, consistently followed, is very important in building stakeholder confidence.
Even if the initial release must contain all the features, you'll still want to take an iterative approach, identifying the MVP for yourself and incrementally adding features. Why? Because right from the first minute you begin, your sole focus is that first demo.
You already have a technology stack chosen. Ensure that your choses stack supports:
- Fairly rapid prototyping
- Fairly easy testing
- Automation of every phase of the cadence.
V) Epics, Stories, and Sprints
Just because you're working alone and are your own scrum master, don't skimp on the Agile Disciplines and Rituals. Although such rigor will feel ridiculous at times (why on earth should you have a daily stand-up with yourself?), producing the Agile deliverables will give stakeholders a fairly reliable view into your work. This creates (justified) confidence and says (truthfully) that you really know what you're doing. Forget creating an impression - concentrate on doing the right thing and that will create the impression for you.
Some shops take the approach that the whole project is an Epic, and each feature is a User Story. I've experienced environments where the alignment between Story and Sprint was strictly enforced, and others where it's much more lax. Personally I like to align Epics with Features in an Epic(Feature)/Story/Task/SubTask approach, wherein Story and Sprint are aligned. That lets us complete one Story in one Sprint, and permits the assigning of Story points more accurately. Tasks and subtasks make it easier to distribute the work, even though as of right now, there's no-one for you to distribute it to ;-) So what? It's still a good idea.
I hope these few thoughts help you toward a good start.