In order to create a chart in your report select the chart item from the palette view and drag it onto the report template in the open report template editor:
This opens the chart wizard. On the first page select the type of chart you want to add to the report:
In the following example we create a pie chart showing the number of customers per country.
On the next page you can define which data you want to use for this chart from the available dataset. Click next and then Select Data in the middle of the page. Now select the Use data from radio button, which activates the drop-down box, in which you can choose from the available datasets:
Once you have selected a data set you will see the available columns in the Data Preview window. From here you can simply drag&drop them onto the referring positions in the Chart Preview window, either as Category Definition or as Slice Size Definition:
Different options are available depending on the type of chart that is selected. Once you have finished selecting data and defining how it should be used by the graph, continue to the next page in order to design and format the graph.
This is where you can define the appearance of the chart, change the title, adapt the legend, and modify colors, outlines, etc.
By clicking Finish the chart is added to the report template where you can arrange it until it fits your needs. As usual you can preview the chart by clicking on the Preview tab at the bottom of the report template editor: