Ok first I would say open a new free email for just your Paid to read sites.
It helps to start fresh with no junk mail.
ususly the sender is "rewards@xxxxxxx" or "noreply@xxxxxxxxx"
You get used to knowing each one.
The links in the emails are usualy ststed that they are paid or points.
I look for a link that has the Paid to read sites name then either "petrack" or "scripts/runner" or "paid" in them.
You will get used to the format of the mails for each company.
Most paid links after you click them have a timer at the top of the page so you know how long to stay on the page.
Hope this helps