Rule zero!
"The time spent analysing and planning your project before you even 'put finger to keyboard' is repaid fourfold later in the development."
So, what should be done in this planning stage?
Define what your project should do. This is usually a list of the main reports and their content. Sometimes projects do things other than report so define these if appropriate.
Define your first thoughts on how the information is to be entered, by whom, how frequently.
Is this envisaged as a single-user project (you can have multiple stand-alone copies) or is it a multi-user project with shared data?
Analyse your data. If you are inexperienced or if the project is large then I would recommend producing an Entity Relationship Diagram (ERD) before attempting to design a relational database. The ERD will help you further understand your data.
Only then produce a first draft database design - either on paper or use Access to draw it nicely. Test the design by walking through 1, 2 and 3 above to answer how the design fulfils the requirements.
Now you're ready to start.
PS Read up on and adopt a naming convention (suggest Reddick) and a set of standards (not familiar with any published ones - just follow what you like of other people's work) from the start.