How does one change a NS record to TLD .CA?

[Karla]

I came upon this problem while trying to submit a sitemap.xml to Google
and Google responded several times to various site submission a "DNS
timeout" too slow to respond.

I tested the DNS at http://www.dnsstuff.com and it gave a F(ail) report
stating "If your results seem poor, it is most likely due to the 'no
glue' issue. ... and further stated ... "If you change your NS records
to be ones on the .ca TLD, it will fix this problem."

I've no idea how to change a NS record to TLD .CA!

Any instructions (in lay terms) or links to some would be greatly
appreciated.