Here are the corrections for the text you provided:
1. First, prepare a purchase manual that can help follow a standard system and procedure.
2. Simply report regularly with supporting evidence of your performance.
3. Highlight the ways to keep regular and alternative suppliers from whom you can purchase.
4. Every time you make a purchase, show the comparative statement of your gain in each individual purchase.
5. Show your genuine interest, honesty, and loyalty. That should be sufficient.
I hope these corrections help! Let me know if you need any further assistance.
Best regards,