1. Find free activities. If you do research, you'll find that there are always some free (or less expensive, at least) museums. For example, in Edinburgh there are multiple free museums and galleries, including the Museum of Edinburgh, Fruitmarket Gallery and the National Museum of Scotland. Most churches and cathedrals are free as well and usually contain amazing art, architecture and relics. I always think it's fun to get off the beaten path and visit the smaller museums or churches that often get overlooked in guidebooks. Another bonus: fewer crowds.
2. Have a picnic. Meals can be so expensive when you travel, especially if you're paying for breakfast, lunch and dinner. To avoid this, we usually look for accommodations that include breakfast in the price. At lunch time, it's fun to have a picnic somewhere. Many cities have fantastic local farmer's markets which are great for picking up sandwiches or picnic things (my favorite is Mercato Centrale in Florence). This can be done at dinner too - how much fun does it sound to picnic while watching the sunset?!
3. Go for a walk. Instead of booking tours, get out and see things on your own. This is my favorite way to explore a city (especially in Venice, when you never know where the next alleyway will lead you) and it's free! I love not knowing what we'll stumble on - churches, ruins, tiny cafes, local shops, an art gallery...
4. Find deals. Check on sites like Groupon for local deals on sightseeing activities, meals and shopping. We just did this boat tour that I found on Groupon for half price and it was great! Looking through these sites before you head out can save money on things that you wanted to do or see anyway.
5. Don't eat at touristy restaurants. We always avoid any place that advertises a "tourist menu" out front. While these menus may seem less expensive, the food is usually sub-par. And there's nothing worse than spending money on something you don't enjoy, especially when you're on vacation! Ask locals or at your hotel for a restaurant recommendation instead. Small places, not in the guidebook, are usually less expensive because they haven't been "discovered" yet or else the prices are kept low to keep local clientele returning. We always share dishes too - that way you can try more things - and we usually ask the waiter what he or she recommends; they'll know that the chef's specialties are or what's the freshest that day and that way you'll get the best bang for your buck.
**This post was done in collaboration with Personal Capital.