What is the appropriate wording to write on a sign to urge people not to litter in front of the mosque?

The Sharia commanded the elevation, veneration, and purification of mosques, based on the Almighty's saying: "In houses which Allah has permitted to be elevated and in which His name is remembered," and the Prophet's saying (PBUH): "Whoever removes a harm from the mosque, Allah will build for him a house in Paradise." It also prohibited everything that contradicts their veneration, including foul odors, buying and selling, and announcing lost property, based on the Prophet's saying (PBUH): "Whoever eats from this plant – meaning garlic – let him not approach our mosques," and his saying regarding lost property: "May you not find it; mosques were built for what they were built for." Therefore, taking a place in front of the mosque where refuse and waste are thrown contradicts the veneration of the mosque and harms the worshippers, and this is impermissible.