create a Workflow on a entity such that new reocrd is created , the system should increment the value of a field on form

Create a Workflow on a entity such that new reocrd is created , the system should increment the value of a field on form 

1.created a entity with two fields and add that field on form and save it and publish it

2.Now  create a work flow for increment a value of field when record is created 

3. Goto Setting---> Click Process

4.click on new small popup will be open 

5.

6.fill the all details like name and category and select entity on which you have to write a work flow

7.after all this step small window will be open

click on Convert to real time work flow

8.click on add step and select update record

9.

10.click on set propertise it ll open a window which display all fields of a form 

11. click on field on which u want to increment a value on right hand side their is dropn called operator click on that drop down you will get list of operation click on increment

12.activate work flow and publish it.

13.

14.final ouput will look like this.