This is the split attention exercise for presence. It is widely known as The Clock Exercise, The Split Attention Exercise, The Three Minute Idiot Exercise, or 12 O'Clock High. Split attention is essential to any mystical path although it can be described in wildly different ways. This exercise is quick trick to produce awakening that works by not working. It is quick if it works right away.  It is slow if it takes a long time to be able to do it. It works by not working because at first people can't do it even if they think they can.  When they realize they are not doing it that is a key step forward.  With persistence though you will become a master of split attention. This is a very big thing.

In this version put half of your attention on the moving second hand.  At the same time, put the other half on the source of your attention.  Split attention is like an arrow pointing in two directions:
                              

                                 "IT"       ,-'/_____________________\`-,       "I"
                                            '-.|"""""""""""""""""""""/.-'

That source can be different things for each person.  It could be your body or your eyes.  It could be the location of the observing awareness which you can try to locate by pointing at it with your finger.  Hold your hand in front of your face and point at your eyes. The observer is looking out of your eyes and you are pointing at it. Try to put your attention on the place you are pointing to. There is nothing there to see but a dark or empty space in which the observer seems to be located.  You can use that empty space with an observer in it as the source of your attention, You can also use your sense of "I", of being a person with awareness, as the source of your attention.  Check that you know that you exist as an awareness. Try to locate in space the knowledge that you exist or the awareness that knows that.  Wherever that is can be taken as the source of your attention. Remember how you managed to locate the source of your awareness so you can find it again!

Once you find something to use as the source of your attention you can proceed. As the second hand moves you see it moving and at the same time are staying aware of the source of your attention. The second hand moves continuously so there is always movement to observe.  

Your attention will drift away from the either the second hand or the source of your attention or both. You may even completely forget you are doing an exercise, lost in thought!  When you catch yourself no longer with split attention simply start over.  Relocate the source of your attention the same way you located it at first. Try to keep track of how many seconds you keep continuous attention simultaneously on the second hand and the source of your attention. 

When done very well there can be an effect of the second hand slowing down and even stopping for a moment.  That is a good sign.

The aim is to be able to do this without interruption for three minutes.  Good luck!