How to add APNS certificate and create the p12 file.

First start with how to create the certificates:
http://quickblox.com/developers/How_to_create_APNS_certificates

then how to export them into P12 format
http://faq.appaloosa-store.com/knowledgebase/articles/61785-how-to-generate-push-notification-p12-file

done!