The bible describes angels as looking like anything from presence of light or simply an angelic presence that the human eye cannot see but feel, fire(the presence of God himself was fire actually and a light so bright they fell to their knees and buried their faces to the ground because the presence scared even the most brave man), animals, humans or a even a combination of both. So to answer your question, angels aren't earthly beings with a specific or assigned physical appearance, they are heavenly messengers of God and can manifest into any form God sees fit.
They don't all look the same. Just like not all humans, animals, insects look alike.
Sounds like they're really big. Some have wings. They're natural form doesn't look human though.
They definitely don't look like some chubby little toddler that the world portrays them as.