Along with copious amounts of birdseed, I feed suet cakes to my garden birds. Which costs upwards of $1 per cake. i love watching Woodpeckers and chicadees doing acrobatics as they poke the suet cags and gobble up the stuff, and they do it while hanging from branches. The scourge of my garden has always been the squirrel and large pest birds (cats too, but that's another story i cover). I use baffles and place bowls on stands that they can't climb onto. I buy suet by the case, and I average 2 cases a month, even while being frugal. That's 24-30 cakes per month for front and backyard habitats.

I sometimes get wise and dig up my homemade birdseed suet cakes recipes that I use in the winter when i have time to do it. It's quite simple. Not as hard as the store-bought, but it doesn't affect things much. I put a cake in the bowls of 2 broken birdbaths on plant stands, and break it up into chunks, mixing regular seed in and over it. That's for birds who forage at ground level and don't eat at feeders. But all birds like eating from platforms. And hiding chunks in the seed mix makes it more foraging fun.

Ingredients

Makes about 14 cakes/or 18 scoops full. Make a nice batch for the freezer, or halve the recipe, if you wish

1 cup beef suet, unflavored vegetable shortening or lard - I use the shortening. It's much cheaper and easier than buying beef suet, or rendering meat fat and the birds gobble it up just as quickly. My grocery doesn't sell suet, so i'd have to make my own. No time for that.
Vegetable shortening is very cost-effective to buy a lot at a dollar store and store it.

4 cups uncooked oats

4 cups peanut butter (if not adding fruit and nuts, use chunky style peanut butter) - store-brand or from your dollar store makes this affordable.

4 cups beef broth

2 cups cornmeal

1 cup or more dried fruit and nuts, seeds, raisins, cranberries - just about anything added to it will make a bird happy.
Hint: When I have it, and i usually do, I just mix a whole batch of inexpensive trail mix into it. Costs way less than buying individual bags of dried fruit and nuts.
Granola is cool, too. Use your imagination when adding goodies. Lots of stuff can be found already in your pantry.

Add some bacon grease if you have some laying around.

3 cups any type of wild bird seed, so use the least expensive.

Optional addition- Hot pepper flakes, or cayenne. They love hot pepper, and squirrels do not.

Instructions

In a large pot or stockpot, combine the shortening or lard, oatmeal, peanut butter, broth, stirring frequently.

Heat to a boil, then reduce to a simmer.

Simmer for 20-30 mins.or until mixture looks like thick oatmeal.

Stir in raisins, nuts, various seeds, berries - anything you wish as an extra addition

Remove from heat and stir in bird seed. Let sit until just cool enough to safely pour into whatever you're using as a mold or container..

Pour into molds or containers, and put in freezer, cooling until hardened. I like to save and use the small, square containers from microwave meals to make my own molds. I also use small square baking tins, tart size, to make them look pretty. The silicone baking molds are great for shaping cakes.

You can also freeze the mixture as a big brick or tube, and cut it after thawing it just enough to cut it into the shapes and size you need. Those hard black plastic trays that fresh meat comes in are really good for freezing large rectangular or square batches. You can certainly opt for putting the mixture in ziplock bags for the freezer. Another good mold would be ice cube trays to make smaller pieces to fit into smaller items you're using as feeders. Thaw slightly, and they can be popped into cylinder feeders easily and no messy hands.

Thaw cakes a bit before serving them to the birds. Leaving it partially frozen makes it easier to cut or place into the feeders without making a gooey mess of it. And birds don't mind.

Store thawed cakes in refrigerator for up to one week, or freeze again with a sheet of wax paper separating them

After just a little thawing, I sometimes get fancy and use my ice cream scoop or my large meatballer to make round cakes to slide into cylindrical feeders

Cornbread Dessert

Another simple food to feed your birds was discovered on refrigerator cleanout day..... I love cornbread. If i bought or made a loaf, there's usually some going into the trash because i kept it too long. I seem to make the corn muffins easily disappear, but the loaves aren't always finished.

You can just let it sit out for a few hours to dry it and crumble it, or repurpose it into a dessert for the birds.
If i have bacon or other meat fat drippings, i crumble the old cornbread into a bowl, stir the stuff in with some fat, seeds or nuts, and put a bowl of the mixture on the platforms i use to hold bowl feeders that keeps it away from  vermin like squirrels and other rodents. It's never around long enough to attract bugs

If you don't normally have the dry, old cornbread problem, the dollar stores usually have corn muffin mixes that are quite inexpensive. Bake the prepared mix as instucted, in a loaf  shape or muffins, adding bacon grease, nuts, berries or seeds to the mixture then, bake as usual. Fast, easy, inexpensive dessert for the birds.

Download a .pdf file of a Wild Birds Food Chart to see which birds like which  foods best.

oops...I almost forgot to mention how to make the easiest bird treat "feeders". 

The traditional Christmas garland with strung popcorn and any type of firm berries, dried or fresh orange and apple slices (they have a natural "hole" to weave wire through). and day-old bread/ firm but not crisp cookies that are going stale. Instead of using twine, which will fall apart in the weather, I use thin green floral or craft wire. It's handy for wrapping around and securing some pieces of the food that might start to wander. Be sure to wrap and secure the ends so that little birds don't get injured or tangled in the wire. I wind the wire widely, so that when the garland starts to get bare, little birds don't get caught in holes they can't think their ways out of. 

Many types of wreath and floral arrangement wire forms can be fitted with food and wired inside or out, as well. If you don't have squirrels, rodents or bears around, secure the garlands around  shrub or tree branches, or hang a few on a tall shepherd's hook to place in different places in your gardens. I used a vintage wire minnow basket one season, filled generously with the weekly toss-away stuff and hung from a branch.