Anticipating and preparing for your important work is a great habit.  It gives you lots of time to think through things and delegate effectively.

If you leave things to the very end, you will find you will spend more time, energy and frustration in completing your tasks.  It is difficult to delegate at the very last moment.

In planning and anticipating, you want to schedule adequate time for important activities.  There is a tendency in many to focus energy on the urgent and immediate, irrespective of how important the activity is.

When I have a speech to do, if I plan way ahead, I am able to do my research adequately and am ready and excited for the job.  If I leave things to the end, I am not as effective.  The same applies to all walks of life.

When it comes to giving, you can plan your activity around it as well.  Also, you can be spontaneous in giving so long as it does not take you away from another important activity that you are in the middle of.