we get lots of these out at a campsite I stay in in western NY every summer. We noticed they liked the bright colors on the tent awning and got a feeder for them; delightful to see them coming by all day...
We just used the pre-packaged mix they provide and add the amount of water per measuring scoop (also provided); it is also colored red which helps the birds to see it...

Be sure to change the mix as soon as the color fades (which it does quickly in the sun!) Enjoy your new friends!