Ironically, as I sit here and write about self-discipline I am also procrastinating on work as I am super tired today and lack the needed self-discipline to trudge through work.
Anyways, I've always lacked self-discipline in my life. When I was younger I was quick to spend what little allowance I had because I had to have those Pokemon cards now!
My insatiable sweet tooth caused chronic headaches and permanent dietary problems.
My love of caffeine (and still love of sugar) caused stomach issues and more headaches.
My need for pain relief caused me to take too many ibuprofen and caused an ulcer and again, permanent dietary issues.
Growing in discipline has been a long journey and I'm certainly nowhere near the end yet! In the past year I have successfully limited myself to no more than 1 energy drink a day and this month I have been trying to cut it out completely as much as I can. So far I've only had 2 so 8 days without caffeine is pretty good!
To close, building self-discipline is hard, but it's important to just keep at it and not give up or beat yourself up because you "failed". It takes time and effort to build a new routine or acheive a personal goal.
Find a system that works for you and (in the words of Shia Labeouf) do it!