Php with zoho invoice api

Php with zoho invoice api

I am new in zoho invoice api.

I would like to create a new invoice by the following step,

Step 1 : html form post data to php script,
Step 2 : PHP script send the data to create a new ZOHO invoice throw ZOHO invoice api.

The problem I am facing is that I can't create a new invoice by doing all this.

I would like to have a simple example(minimum data need) of that php script to create a new invoice.