Definitely buy things like cheese, veggies, and fruit whole and cut them yourself. Party trays are a huge waste of money. Things like humus are also easy to make yourself with a food processor (cooked drained chickpeas, olive oil, garlic and/or red peppers to taste). Humus stays good in the fridge for a while. Pita chips are also easy to make yourself (buy or make some pita bread, rip it into smaller pieces, drizzle with olive oil, sprinkle a little salt or garlic salt of them, and bake until they're crispy).

Also, seriously, don't go nuts on wine. A lot of people (even wine snobs) can't really tell the difference between the $30 bottle and the $10 bottle. Buy the $10 bottle (grocers can often recommend a good bottle under $10, or there are many reviews online) and decanter it. No one will know the difference.

I do save money by cooking at home, and I've built up a pretty big repertoire of dishes.
But the main ones I like to make to save money and that will last for a day or even two before using are salads and dips.

Rice salads - cold savory rice with diced or chopped vegetables and spices with your favorite salad dressing, lasts for days in the fridge and tastes great after hours of marinating.

Pasta salads - same deal, chopped vegetables in spiced plain pasta with salad dressing. I use whatever I have in the fridge and even a bit of pesto and cheese is fabulous, cheap and easy to make.

Potato salads - you can do all sorts of different types, try french dressing instead of cream dressing, with loads of garlic! Just divine and best after a few hours or day in the fridge.

Dips - packet soup of choice ( chicken, french onion, mexican ) and either cream cheese for those who can eat lots of creamy cheese, or cottage cheese for a low fat option. Add cumin powder or curry powder to the mix and away you go! Serve with crusty break or crackers! Sprinkle fresh herbs on top! Looks great and easy to make.

These help me out when I need to feed a few people or when I need to take something to a party to feed heaps of people ... and cheap!

Try Asian dishes.

Asian dishes usually use cheap ingredients and seasonings, filling, and they spread the meat, which usually cost the most. My family is planning, like almost every New Year celebration, to cook shabu-shabu. You just prepare the raw ingredients, a pot, and a portable stove in the middle of the table. Sit around the table and everyone can cook for themselves. It is very healthy too.

For people like me, who often take use credit or loans, having a high credit score is a very good way to save money. Everyone knows that credit score is vital for getting a better APR but few people realize how much that 1-1.5 % difference really is. Imagine you take a 50K loan. For the first year, a person who took it with 1% higher APR will pay $500 more. Each year that will go down but by the time you pay off this loan you'll have paid several thousand dollars more because you had lower credit score at the time you took it. Now that's not a small amount on money.
http://www.financemetrics.com/best-way-to-save-money-irrespective-of-your-income/