Insert the image or table into your Word document. Right-click on the activated element to select: "Insert caption...".
Now enter a brief, comprehensible description there, just as you would for headlines - example: "Sales development 2004 to 2014".
This title then appears automatically in the corresponding directory (for figures or tables), maintaining automatic numbering ("Figure 3" or "Table 3").
You do not place the source reference in the description text of the illustration, but below the illustration in the first line of text, and from there refer to the source in the form of the short document. Example: "Source: Müller 2014: 38".
This source must, of course, appear correctly in the list of sources, provided it is an external source. If you are working with a literature management program such as Zotero, this is guaranteed.
If your insertion is a complete self-representation, write in the text line below the illustration: "Source: Own representation"; then no entry is made in the source directory which, as is known, may only contain published information.
However, if you have created your own table that reproduces parts of a representation already published somewhere, the specification is: "Source: Own representation based on XYZ".
Note: Source references and short documents do not belong in the tables and tables!