theres no one way to do anything, youll notice kermit said 'its not advisable' that doesn't mean he said its impossible to take a clone from your plant. you can do it, your chance of success is a little lower than if you took it before flower or 1-2 weeks into flower but it could still root. i just took two clones from a flowering plant that is about as far along as the one in your pic, it rooted in 2 weeks. i didnt chop the flower or cut any leaves, there are no hard rules in growing marijuana. you ask one question youll get 100 different answers. the problem is that marijuana is illegal in most places and unlike say a tomato plant, there isnt any scientific studies that we can point to that says 'this is the best way to go about doing this or that for marijuana'. most everything is trial and error but we can take some things learned from other type of plants and apply it to our mj.
personally id cut it one node lower to make the clone a little taller. i wouldnt take the flower off or trim any leaves. if you get it to root and reveg, the little flower on top will send out many new branches and the clone will grow very bushy, unlike the mother plants tree structure. some people call it monster cropping, i just call it revegging.