I found one of the key elements to volunteering for an extending period of time was doing so on a regular basis.
If a few weeks passed and I had not gone in to volunteer, the whole process became more difficult. I did not feel as comfortable with my duties, others people may have forgotten about me (or new people might be unfamiliar with me), and just more overall effort was required to pick up where things left off. An analogy is not going to the gym for 2 months and then trying to go back. It is hard and no fun at all.
When volunteering, I think it is important to go in on a regular basis. Try missing one week at the most, when I missed more than two weeks, that is when things became difficult for me. And of course, the organization or cause that you are helping will be very happy to see you there each week!
