Most importantly have your camera you use to hand at all times. Have a place you keep it and make that somewhere you’re very likely to walk past as you head out of the house. This means you can pick it up almost without thinking.
Did you know that on average if you follow a habit for more than 20 days it will stick?
Once you’re out with your camera have a theme in mind, keep this nice and simple. For example pick the colour red and while on your walk look for everything in that colour. You’ll be surprised with what you capture and will probably ended up photographing things they usually would just walk past.
One last piece of advice is to have somewhere to output your photos. This can be Facebook, Twitter, Instagram, Flickr or even your very own blog. I find that having a goal in mind not only gets me photographing more, if I have somewhere in mind to put them it also gives me an extra motivation to get out and take more photos.