I am really confused about the difference between a design brief and project proposal and when I should use them during the collaborative design process for print and website projects. And I have tried to search online but I've seen them used interchangeably. I do not know the difference anymore. Can somebody please explain this to me?
The clue is in the name. They address different things.
The design brief covers just that: design. This is where you discuss, determine, and otherwise find out things like:
- what the client likes (blue, high contrast, side menus) and doesn't like (green, animated transitions, autoplay video)
- the physical logistics of the job (is it a WordPress site or HTML5? Is it 6x9, a business card, or A4? a suite of stationery or a one-off flyer?)
- the goal of the job
- what counts as a conversion, or success
- who is the client's audience
- who is the client's competition
A report after such a meeting would cover all the artistic parts of the job.
A project proposal covers the entire job, and design is only mentioned insofar as it's a line item saying "Project is Designed and Client chooses a design." It is literally what you are proposing to do for the client's job. You can have a project proposal for something which has no actual design involved (a pure production job where you take the client's files and print them, for example). It's more than a scope of work and not quite a contract, and might overlap both. It describes the things you are going to do, the things the client is going to do, and what isn't included and will cost extra if the client wants it. For example:
- Description of the job (website of X pages, stationery suite, six flyers, poster, corporate ID)
- Procedure for the job (meeting, evaluation, Designer provides comps, Client chooses comp, Designer creates final, Client approves, Designer delivers)
- Payment milestones
- Number of rounds of revisions
- How Client is sending assets, and deadlines (e.g., within 10 business days of Designer request)
- Project deadline
- Kill fee or other cancellation procedures
- Items which are explicitly not included
As far as when: your first meeting or two with the client is the design stage, where you figure out what the job is going to be: the shape, the scope, what it's going to look like, the deadline. After that you can determine the project logistics: we know what we want to do, and here's how we think we can execute it.
There are good answers here about what goes into a job contract, some of which can also apply to a project proposal.