These fly patterns are more traditional dry flies. Flies like Greenwells Glory, Beacon Beige the traditional hackled dry flies have been used for many years on many of the southern chalkstreams. Hackled trout flies are often traditional patterns that have been used by fly fishermen for many decades.
Simply use a tapered leader with a floating line and cast your fly. Be careful to mend the line to avoid the current dragging the fly, it needs to look natural as it drifts to any nearby trout and grayling. If the line drags then a simple flick of the line upstream so that the line and leader do not drag, this is normally sufficient to stop the drag and make sure it is presented naturally.