ow you can publish the extension to the Visual Studio Gallery.

Make sure that you have built the Release version of your extension and that it is up-to-date.
In a web browser, open the Visual Studio Gallery website.
In the upper-right corner, click SIGN IN.
Use your Microsoft account to sign in. If you do not have a Microsoft account, you can create one at this point.
Click Upload.
In Step 1: Extension Type, select Tool and then click Next.
In Step 2: Upload, you can choose to upload directly to Visual Studio Gallery or just add a link to your own website. In this case select I would like to upload my tool. The Select your control box appears. Click Browse and then select TestPublish.vsix in the \bin\Release folder of the project. Click Next.
In Step 3: Basic Information, fields from the source.extension.vsixmanifest file are displayed. Select an appropriate Category and add Tags to help users find your extension. You may want to add a more detailed summary and description (the description must be at least 280 characters long). Leave Extension Type as Not a Microsoft Extension and Cost Category as Trial.
Read the Contribution Agreement at the bottom of the page and check I agree.
Click Create Contribution. This displays the page your extension will have on the Visual Studio Gallery, with a message that the page has not yet been published.
Click Publish.
Search the Visual Studio Gallery for your extension. The listing for the TestPublish extension should appear.