How do i do this?

lots of people mention it as a good way to get rid of the dredded red numbers that never go..i currently have about 6 sections where this hapopens.

This section
Suggestions
Key general threads
Traders
and the FFST merch thread

all have red numbers everytime i log on ):

Go on My Home and there is an option in there down the bottom

the only way i got red numbers on certain threads to go away was to clear my browser history while logged out, then make sure i do mark all read as the last thing before I log out each time. If i stay logged in, these unread threads will keep popping up

No red numbers for me, ever..............dunno how or why tho

I still get them on some threads, I'm just used to it now