Hello, @userjuangovelez.

Right now, setting up discounts would advisable using a browser. I'm happy to provide detailed steps on how to apply 10%, 20% into your transactions.

Here's how: 

1. Go to the Gear icon, then choose Account and settings. 
2. Select the Sales tab, then click Edit in the Sales form content.
3. Turn on the radio button perpendicular to Discount. 
4. Tap Save, then Done. 

After that, let's create a sample invoice or estimates to see how the discount looks like. 

Here's how: 

1. Go to the + New.
2. Select Invoice or Estimates. 
3. Complete the required information. 
4. Enter the exact percentage, then Save and close. 

For more details, check out this article: Add a discount to an invoice or sales receipt in QuickBooks Online.

You can always open the Discount given in the Chart of Account to review all the discounts you've used for your clients. 

Additionally, please browse these articles below about managing sales transactions, customized forms, and other topics: 

• Sales and customer.
• Mobile applications hub

You can always leave your comments below if you have other questions. I'm always here to help.