mybikeisace:
I think it is going to be rather difficult for anyone here to tell you how to design your database without know a lot more about your project.
If you want a field in your database for every day in the year then you are going to have at least 365 fields. However, it depends on what you are going to use the database for.
If it is for some type of day planner you might need to keep track of the hours within any given day. Or, if you are keeping track of rental cars then you may have several transactions for each day.
If you are just keeping some sort of personal diary about what took place each day then that is another situation. Maybe you would only need two fields such as date and activity.
Like I said, without knowing what it is you are trying to do I don't think there is much information anyone can give you that will be very helpful to you in designing your database.