1 - Open Sidekick and go to the Letters to Tenants Section.
2 – Select a letter from the report/letter list and click the Edit button at the top of the list.
3 - At the top of your letter you will see a set of icons for inserting. Put your mouse over the icons until you find the one for "Insert Merge Fields". When you click it you will get a list of Sidekick merge fields. Click on the one you want and it will be inserted into your letter where you want it.