We are currently working on getting the Integration Glue Micro Apps into the HubSpot Marketplace
In the mean time you can Install from the Integration Glue app.
If you are a new User click the + Create Account button and enter your Account Name and Main Billing Email
Under Apps, click the Available tab
(Make sure you are logged into HubSpot)
Click the Install button next to the App you want to Install
Select the HubSpot account to install the app on, and click Choose Account
Click the Connect app button