I am somewhat of a spender. What I have to do to limit myself is not to bring my wallet with me when I go shopping (or to school in the morning), as well as only spend cash within a paycheque. My wife and I went for some snacks last night and I said to her "I think this is the first time in the last year that I have used my debit card".
Nonetheless, in order to manage my cash I have decided to create "jars" or "buckets" of money that I will contribute to each paycheque and then spend out of them from day to day. When the cash is gone, I have no money to spend. It is a great system to me and has allowed me to limit my spending.
My most important bucket that I have created for myself in 2010 though has been the "XMas Bucket". Now, you may be asking yourself, isn't it June? Why is Christmas so important to you in June. Let me clarify myself: this cash isn't just used for Christmas, although it was the original intent, it is used for gifts all through the year. So when people have babies, or it is Father's Day, or you go to a wedding or whatever, you don't put yourself in the hole because of it. It is also always good to have some spare cash laying around so that you can take part in these wonderful events as the year progresses.
On the negative side, my goal was to have Christmas entirely paid for before hand. For 2011 I will probably have to create another bucket for Christmas (because that is definitely my biggest gift giving time of the year) along with my generic gifts bucket, so I don't go into the hole around Christmas as usual.