Form 16 of two employers

Hi All

Last FY, I worked for two organization and hence have two form 16. First employers didn't consider any HRA exemption while second employers considered HRA of only the period I worked with them. 

Now while filing IT Return I want to claim my HRA Exemption which was not considered in Form 16 of first organization.

Please let me know the steps to claim HRA exemption.

Note:- I am filing ITR 1

Thanks

Rajesh