Keep away form jealousy for jealousy eats away piety the same way fire devours wood. (Abu Dawood)
Even greeting someone with a smile is charity and holds good deeds (Tirmizi)
A Muslim who removes the anxiety of another Muslim on this Earth, Allah will remove one of his anxieties on the day of resurrection. (Abu Dawood)
Do not be ashamed of doing any good deed even if it is small. For doing something is better than doing nothing. (Bukhari & Muslim)
Do not boast about your dead ancestors to suppress others. All mankind are children of Adam and Adam was created from dust. (Tirmizi & Abu Dawood)
The ones most disliked and stated furthest from me [i.e. The Prophet] on the day or resurrection will be the ones who are boastful and big-mouthed and speak unnecessarily. (Tirmizi)
If you speak of a person behind their back and that evil is not found in them then you are guilty of slander. (Abu Dawood & Tirmizi)
If you love someone be moderate in showing your love for he might become the cause of your anger someday. (Tirmizi)
When one of you yawns they should place their hand over his mouth. (Muslim)
Do not express pleasure at the hardships of others. Let it not happen that Allah release them and involve you in it. (Tirmizi)
He who gives up disputing while he was on the wrong will have a palace built for him on the edge of Paradise. (Tirmizi)
Do not sit between two men without their permission. (Tirmizi)
Each of you is a mirror for his brother. Therefore if anyone finds a stain on it he should remove that stain. (Tirmizi)
Respond to him who sneezes three times with Yarhamak Allah. But if he sneezes more than this, you may not respond to him if you like. (Tirmizi)
A Muslim should not tyrannize any people but instead he should help them. (Abu Dawood)