The pursuit of a positive experience can be as simple as taking a walk. Step out (and step up) for something you believe in, and the experience can be all the more powerful.
Community-based activism can take many forms. Organized walks and marches are a popular method of raising awareness for a cause while sometimes raising funds as well. Making a commitment to participating in this type of activity can be a simple way to take a stand while enjoying some time on the town. You get the benefits of being out and about, plus you get a sense of social responsibility and a chance to make new friends who share your outlook (whatever that may be). If you are feeling ambitious, you might even consider organizing your own neighborhood (or worldwide) rally.
Regardless of whether you simply show up to be counted or you proactively lead the charge, you will have accomplished something worthwhile for the betterment of yourself and your fellow travelers.

Bonus: DIY Sign

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For an overview of accumulating positive experiences click here.