I decided to give APO a go on my website and found that there was no difference in speed or TTFB. I contacted support and they told me it was because my cache control header was set to max-age=0. What is the easiest way to add the correct headers to a WordPress site and what values should I use?
EDIT: I have managed to figure out how to add the headers by using:
Header set Cache-Control “max-age=604800, public”
Is that a correct max-age value?