In that order mate.
Basically, you need at least a polish to clean the paint (I used the clay to thoroughly clean of all contaminants and strip back the wax). Having clean paint is the key to getting the sealant to bond to the surface - if this is not achieved the whole process is thoroughly compromised.
The sealant then forms a tough dureable layer over the polished surface (it's like a thin plastic layer) then this particular wax protects the paintwork like nobodies business! Other types of waxes are mainly for looks but the Collinite is very durable and still adds a great reflective shine. Shouldn't need to do much now apart from washing, quick detailing and a possible wax top up over the winter but that would be for looks rather than protection.
Hope that helps.