Once you have set up your NetSuite instance with the correct permissions (how to link here) required for a NetSuite connections follow the below steps to add the SuiteApp
Login in to your NetSuite instance
Search for “SuiteApp Marketplace” in the top search bar
On the small left-side search bar, search for “Kolleno”
4. Click on the result “Kolleno”
5. Click on the blue button “Install” on the right-hand side
6. If you do not have a Kolleno account, simply create one here: https://app.kolleno.com/signup Otherwise, go directly to Step 7.
7. In the Kolleno platform, head to your accounting settings https://app.kolleno.com/settings/accounting/
8. Click on “Connect” next to NetSuite and follow the flow on the screen.