You can learn more about Tag Groups here. In this post I just want to cover how you would go about adding contacts to a Tag Group in bulk.
From your Advanced Search page, after running a search that will include your desired contacts, place checks to the left of the names of those contacts that you want to add to your Tag Group:
Then, click the Contact Options menu above your search results and select Bulk Actions:
Next, select Add to Tag Group from the Bulk Contact Actions modal that appears.
You'll then see the Add To Tag Group modal, where you can then create a new Tag Group or choose from your existing Tag Groups to add your selected contacts to:
To add to an existing Tag Group, or to multiple existing Tag Groups, you would just place checks next to that group or groups and then click Add to Tag Group:
In the above example, once you click Add to Tag Group, these contacts will be added to the "401(k) Clients" and the "Newsletter" Tag Groups.
Now, if you want to add these contacts to a new Tag Group, you'd just type the name of that new Tag Group in the box at the top and click Add to Tag Group at the bottom:
In the above example, you're accomplishing two tasks at once. You're creating a new Tag Group called "Source of Referrals" and you're adding your selected contacts to this new Tag Group.
As you can probably see, it's a quick and easy method to group your contacts in ways that can really help streamline the processes in your office.