In order to place an order, you first need to check if the Online Market is still open or not. Depending on which day the Collection takes place, the Online Market will close in the evening two days previous to the collection (i.e. If a collection takes place on Wednesday, the Online Market will close on Monday evening).
When the online market is open and you just logged in, simply click on "Choose the Products" and you will have access to the different product catalogues available. Choose the products you would like to collect, go to the check out, pay the order and you are done! Your orders will be expecting you at the next Collection!