You can easily create your own group on LinkedIn by clicking on the group tab and then "Create Group" from the drop down.

When making a group, there are a few things you should keep in mind. You don't want it to be the name of your company or brand, and you want to make sure it'll appear in Google search results as well - so that mean going back to keywords and making sure it's something people are already looking for.

Make sure you build a group around the audience you're looking to attract.

After that, it's a matter of filling in the group details page:

I like to make sure that the group type is set to "Networking" and further down this page, you should also set the Access to auto-join so that you don't need to manage the invites and you'll have a more dynamic group with more people joining and posting.

I also like to make sure the group is location agnostic (so leave the location check box unmarked) - this will allow more people from anywhere to join it. Then finally, click the Twitter box to send out and announcement about it to the account of your choice, accept the terms and click the "Open Group" button to allow anyone to leave a comment or post into the group.