First, the basics:
Define a summary field as the "count of" some field in your lineitems table that is never empty such as a Product ID field.
Set up your chart object to use the color field as the Horizontal X axis. Use this summary field as the Y axis. Then select the Use data from current found set and show data points for groups of records when sorted options.
Put this chart object in the body of your layout and sort your records by the color field. You can limit what data is used in the chart by using a Find to pull up just the records you want, such as just the records for a specified date range or only specific products sold.
If you want to see multiple charts--one for each day of the week or each month, you can this same chart in a sub summary part that sorts by a field that will group your records by week or month. This may require adding a calculation field that allows you to group records into those categories when you sort the records.