Yea, I save money on fast food by just not eating it all that often! When I do go, I don't really bother with wanting to save money and just get what I want. The dollar menu is the best value as far as quantity concerned, but not really all that good of food. I also never buy drinks at fast food places and just stick with drinking water. That usually saves $2 every meal as well.
When I am trying to save money on fast food I usually use coupons. My Sunday paper usually has coupons for the local fast food restaurants. If I am not able to find a coupon than I look at what is available on the dollar menu. Sometimes you can create you own meal off the dollar menu and only pay about $3.00.
Coupons and vouchers are a great way to save on food. I don't always look for coupons because sometimes even when I have clipped them I would forget to use them. They have an expiration date that you need to pay careful attention to. Another way is to find deals when eating out. Be on the lookout for deals, including making use of discounts and special occasions.
Coupons help, but like others have stated, I usually choose from the "value" menu (can't hardly call it a dollar menu at most places any more, lol). I also skip the drink. I usually bring a drink with me if I'm out and about anyway. I skip the drinks at most restaurants these days, since they charge so much for something that costs mere pennies to make. Plus, they pack it full of ice, and you get more ice than soda. So, skip the drink or ask for less ice.
Yeah very rarely will I get a soda even at a place I'm dining in. If I get something it's usually a smoothie or something like that..something I can't get easily at home.
We try to eat at home as much as we can. Sometimes I really want something from a fast food restaurant so when I see coupons I keep them. I also try to order off of the $1 menu, even if I need to buy 2, it's still cheaper.
I think the best way to save on fast food is to not buy any at all. The nutritional value of it is debatable and the ingredients are highly dubious. Many multinational companies use GMO ingredients and their ethics are questionable. So, instead of trying to save for a burger, why not invest that money in some healthy bulk food from a health food store? It will go a long way.