Jawas are meter-tall humanoids completely hidden behind rough, hand-woven robes. Their faces are concealed within the dark folds of a cowl, from which peer their sickly glowing yellow eyes. They comb the deserts of Tatooine in search of discarded scrap and wayward mechanicals.
Using their cobbled-together weaponry, they can incapacitate droids and drag them to their trodden fortress-homes, immense sand-scarred vehicles known as sand crawlers. They sell their hastily refurbished junk to moisture farmers who are hard-pressed to find a better selection elsewhere.
The robes, those are used much like the ones from Dune, to hold in moisture, hide their identity and to dissipate their body heat.
The glowing eyes they seem to have is the result of polished orange gemstones that are sewn into the robes to protect the Jawas’ eyes from the bright sunlight (no mention about WHY they would evolve such delicate eyes in such a hostile environment).
The robes are also soaked in some liquid which smells awful (to us), but helps keep them hydrated, and helps them communicate (with smell).