Discounts can be added to invoices, bills and estimates both on a per-item basis and to your statement subtotal. We'll go into both options now:
Adding discounts to line items:
In order to add a discount to a single line item, click the discount button located in the righthand corner below your line item name and description field. After clicking on this button a popover menu will appear, allowing you to either use a saved discount or to add a new one. If you're adding a new one, please enter a discount name and its rate. Your discount rate can either be a percentage (e.g. "10%") or a fixed amount (e.g. "10.00"). Clicking on remember will save this discount for reuse.
Adding total discounts:
Discounts can also be applied to your statement subtotal. In order to add a total discount, click on the discount button below your statement's "Balance" line. This will add your total discount as a separate line, also allowing you to specify a discount name and rate. Clicking on remember will save this discount for reuse.
Default total discounts:
By navigating to Business Settings > Taxes, Discounts & Shipping you'll be able to see all discounts currently saved in your account. By checking the "Set Default?" checkbox next to any one discount, you make sure to have invoicely add this discount to all future invoices, estimates and bills by default.