Put it in a pretty cup. I sometimes put my water in a wine glass and sip on it as if it is wine or something exotic. Childish, I know, but it does the trick.
Drink a cup before you eat. That's an automatic three times a day (you should be eating three meals at least), so that is three more times than you have been drinking in the past. Cheers!
Get rid of all other drinks and juices in the house. I typically only keep water in the house, so when I am thirsty, I really don't have a choice in what to drink. Water is always my number one. If that is just way too much for you to do, consider setting a time limitation on when you can drink something other than water. Maybe you can only have a beverage other than water between 5 pm - 6 pm or in the morning with your breakfast. By setting a limitation, you aren't depriving yourself of whatever it is you like, but you are still practicing will power.
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I'll Drink to That!