to create a custom table style step is as follows:
Step one: Start Word, create a new document, or open the document you want to edit.
Step two: If there are no tables in the document, you can insert the table like this: On the Insert tab, click Table, and then create a new table. (You can refer to the small written "Word2013 How to insert a table").
Step three: Select the table, and then on the Design tab, set the style, border, and so on for the table.
Step four: Set the table as shown in the following figure.
Step Five: Save the Custom table: Select the table, then on the Insert tab, click Table, select Quick Table from the pop-up menu, and then select Save the selection to the Quick Table library.
Step Six: Open the new Building Block dialog box, set (or leave the default), and click OK.
Step Seven: When we need to insert the type of table, you can do this: on the Insert tab, click Table, select Quick Table in the pop-up menu, and then select the style of the table, for example, select the table you just customized.