Manners

1.DO NOT SPEAK IN A LOUD VOICE

"And be moderate in thy pace and lower thy voice; for the harshest of sounds without doubt is the braying of the ass." [Surah Luqman (31):19]

2. WHENEVER YOU MEET SOMEONE GREET HIM WITH A REAL SMILE FIRST AND THEN SHAKE HANDS WITH HIM

[This applies only when a person meets another person of the same sex, i.e. when two males meet, or when two females meet].

The Prophet (SalAllahu A'lyhe Wasallam) said: If two Muslims meet, shake hands, praise Allah, and ask Him for forgiveness, they will be forgiven.
[Sunan Abi Dawood]

3. CALL YOUR BROTHER BY GOOD NAMES, USING MORE FREQUENTLY THE NAMES WHICH HE LIKES THE MOST. ALSO, DO NOT MOCK OTHERS, WHETHER OLDER OR YOUNGER.

O ye who believe! Let not some men among you laugh at others: it may be that the (latter) are better than the (former): Nor let some women laugh at others: it may be that the (latter) are better than the (former):nor defame nor be sarcastic to each other nor call each other by (offensive) nicknames: Ill-seeming is a name connoting wickedness (to be used of one) after he has believed: And those who do not desist are (Indeed) doing wrong.           
[Surah Al-Hujurat (49):11]

4. WHEN SPEAKING TO A PERSON, YOU SHOULD PAY DUE RESPECT TO HIM AND TALK IN A FRIENDLY TONE. YOU SHOULD NOT DO ANYTHING TO MAKE HIM FEEL ASHAMED OR TO DOMINATE HIM

O ye who believe! Fear Allah and (always) say a word directed to the Right:
[Surah Al-Ahzab (33): 70]

A Muslim is a brother to another Muslim. He should neither tyrannize him, nor hold him in contempt.  [Sahih Muslim]

5.          YOU SHOULD NOT SUSPECT AND BACKBITE ANYONE. IN OTHER WORDS, YOU SHOULD NOT FIND FAULT WITH ANYBODY IN HIS ABSENCE. YOU SHOULD RATHER APPRISE OTHERS OF THEIR FAULTS IN A POLITE MANNER.

O ye who believe! Avoid suspicion as much (as possible): for suspicion in some cases is a sin: and spy not on each other nor speak ill of each other behind their backs.  Would any of you like to eat the flesh of his dead brother? Nay ye would abhor it...but fear Allah: for Allah is Oft-Returning Most Merciful. [Surah Al-Hujurat (49): 12]

6.     LEARN TO ADMIT YOUR FAULTS
He [Moses (AlyheSalam)] prayed: "O my Lord! I have indeed wronged my soul! Do Thou then forgive me!" So (Allah) forgave him: for He is the Oft-Forgiving Most Merciful. [Surah Al-Qasas (28): 16]

The Prophet (SalAllahu A'lyhe Wasallam) said: "When a person admits his fault and seeks Allah's forgiveness, Allah does forgive him."  [Bukhari]

7. SPARE NO EFFORTS TO SERVE OTHERS SELFLESSLY WITH BOTH WORDS AND DEEDS AND, IF POSSIBLE, PROVIDE MATERIAL HELP TO THEM, PARTICULARLY TO YOUR PARENTS AND CLOSE RELATIVES.

Serve Allah and join not any partners with Him: and do good to parents kinsfolk orphans those in need neighbors who are near neighbors who are strangers the companion by your side the way-farer (ye meet) and what your right hands possess: Lo! Allah loveth not such as are proud and boastful. [Surah An-Nisa'a (4): 36]

Allah loves His servant as long as he keeps helping his brother in faith.  [Muslim]

8. CONTROL YOUR ANGER AND ABSTAIN FROM ASSUMING SUPERIOR AIRS

Whenever you get angry, you should say:  "A'oudho Billahi Minash Shaitaanir Rajeem"  
 (I seek refuge with Allah from accursed Satan). 

 Those who spend (freely) whether in prosperity or in adversity; who restrain anger and pardon (all) men; for Allah loves those who do good. [Surah Aal-i-Imran (3): 134]