It sounds complex, but the concept of database normalization can be summed up in three words:
Don't Repeat Yourself
Follow these guidelines and you're 90% of the way there:
- Use an Autonumber primary key in each table.
- Store each piece of data only once.
- Store one piece of data per field.
- If you can calculate it, don't store it.
- Lists of finite choices should be in their own tables and referenced by ID.
One final piece of advice: databases are not simply bigger Excel spreadsheets. Don't treat them as such!