There is a white line or dot on the bottom of the lens hood, align it with the white dot on the lens then twist clockwise. To store the hood on the lens align the pull out tab (used to adjust a polarizer) then twist clockwise again. I once had this lens and the hood on mine was somewhat loose fitting. Decent lens though for a DA.
Tried that. About a thousand times. It doesn't catch on anything! The hood seems to be too large for the lens. Thanks for the suggestion, though.
Discovered the apparent problem. Ordered the 49mm hood which was listed as appropriate but was sen a 52 mm hood. Duh. Many thanks