Hi Louise @LouiseGretalDesigns - as Kim says you can join in at any point BUT you do have to follow the posted link for each shop that’s joining in each day.
That means going to an item in a shop (by following the shops provided link) then loving 
the item, and then returning back to the thread and the post on the thread to say you have loved the item in the shop. You then repeat the process for all the shops that post that day.
The group is friendly and will help you through the process BUT do read the rules at the top of the page - it is time consuming but many of us think it worthwhile and we have some fun along the way.