Border help

[Carolve]

Hi ladies...
It has been way too long since I have been on here, but life has been busy. Please I have been sick with colds most of the winter. Anyway, enough about that. I have a question for you guys. I am having trouble when I put borders on my quilts. Well only done it a few times, but my borders come out wavy and it is driving me crazy. How can I fix this? And what is a good way to avoid this is the future...?

Any help and ideas welcome...

I am posting a pic of a quilt top with wavy borders....

Thanks ladies in advance...I know someone will be able to help...