If you want to have just small bird coming to your yard, take a look at bird feeders for small birds only. There are such feeders out there. However, most birds would probably still be able to eat out of them. If you want to get rid of large birds, make sure that the feeder is as uncomfortable for the large birds as possible. Mesh feeders are great for this purpose. Smaller birds can stick their small beaks inside the mesh, while large ones will not be able to get any food out of it. However, if the small birds will be throwing food out of the feeders, larger wild birds will get a chance to pick the food off the ground.
Best bird feeders for small birds have perches. A lot of birds feel more comfortable feeding while sitting on some perches, than by grabbing food from the air. Also smaller birds appreciate higher feeders. So the higher you place the feeder the better. When you are choosing the bird feeder for the wild birds in your yard, take some time to think about cleaning them. Mesh feeders might be comfortable to put food into and create less mess, however, they are much harder to clean, since the food gets stuck in between the wires. Such feeder will need to be immersed into a cleaning solution fully in order to get it properly disinfected.
If you live in a cold climate think about best bird feeders for winter. When it gets cold, grain gets hard. So, birds will have a harder time grabbing it. Uncovered feeders will get some snow falling on them and the food will get wet. So the best feeder for the cold times would be the one with a roof and not too much space, so it is not covered in snow.