When creating an invoice, you can charge by the hour. Here is the best way to do it.

Go to Settings > Templates > Invoice Items > New Item.

Create an invoice item for 1 hour's worth of work. Set your price, and write a description. The duration is optional, leaving this blank won't affect anything.

After you finish, press 'Add'.

Next, select the project you wish to send an invoice to. If you haven't created one yet, go to the projects tab and select 'Create Project'.

Click 'Add Invoice'. Add the item you just created for 1 hour's worth of work.

In the invoice there is a place for item quantity, here you can enter the number of hours and the invoice will calculate the total amount.

Set what payment types you accept, whether or not you want to charge a retainer, the tax rate, discount amount, due date, and charge method.

After this, create the invoice. You will be prompted to send the invoice. Click "Yes, send it,"
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You will see a screen that allows you to enter a subject line for the invoice email, add recipients, and either copy the URL or open the invoice in a new tab. You can share this URL with your client via text message or email.

After previewing your invoice and ensuring that everything is accurate, you're ready to send it to your client.
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