The following guidelines for living amicably and peacefully with all are taken from Counsels from My Heart by Dudjom Rinpoche. While written from a Buddhist perspective, the practical advice given will be useful for any spiritual aspirant:
All success, great and small, whether in spiritual or temporal affairs, derives from your stock of merit.
So never neglect even the slightest positive deed. Just do it.
In the same way, don’t dismiss your little faults as unimportant—just restrain yourself!
Make an effort to accumulate merit: make offerings and give to charity.
Strive with a good heart to do everything that benefits others.
Follow in the footsteps of the wise and carefully examine everything you do.
Do not be the slave of unexamined fashions.
Be sparing with your words.
Be thoughtful and examine situations carefully. For the roots of discrimination must be nourished: the desire to do all that should be done and to abandon all that should be abandoned.
Do not criticize the wise or be sarcastic about them.
Rid yourself completely of every feeling of jealous rivalry.
Do not despise the ignorant, turning away from them with haughty arrogance.
Give up your pride. Give up your self-importance. All this is essential.
Understand that you owe your life to the kindness of your parents, therefore do not grieve them but fulfil their wishes.
Show courtesy and consideration to all who depend on you. Instill in them a sense of goodness, and instruct them to practice virtue and avoid evil. Be patient with their little shortcomings and restrain your bad temper—remember that the tiniest thing can ruin a good situation.
Do not consort with narrow-minded people, nor place your trust in new and untried companions.
Make friends with honest people who are intelligent and prudent, and have a sense of propriety and courtesy.
Don’t keep company with bad people who care nothing about karma, those who lie and cheat and steal. Distance yourself, but do it skillfully.
Do not rely on people who say sweet things to your face and do the reverse behind your back.
As for yourself, be constant amid the ebb and flow of happiness and suffering.
Be friendly and even with others.
Unguarded, intemperate chatter will put you in their power; excessive silence may leave them unclear as to what you mean.
Keep a middle course: don’t swagger with self-confidence, but don’t be a doormat either.
Don’t run after gossip without examining the truth of it.
People who know how to keep their mouths shut are rare.
So don’t chatter about your wishes and intentions—keep them to yourself.
And whether you are speaking to an enemy, an acquaintance, or a friend, never break a confidence.
Be welcoming toward people, and smile and talk pleasantly.
Keep to your position.
Be respectful toward your superiors, and even when things do not go well for them, don’t scorn them.
At the same time, don’t bow and scrape before the vulgar, even when they are proud and full of themselves.
Be skillful: do not make promises that you know you cannot keep.
By the same token, honour the promises you have made, and never dismiss them as unimportant.
Do not be depressed by misfortune and the failure to get what you want, instead be careful to see where your real profit and loss lie.
All such worldly conduct, adopted with proper discrimination, will result in this life’s fortune and prosperity and, so it is said, a speedy passage to the divine realms.
Source: Dudjom Rinpoche. Counsels from My Heart (Kindle Locations 871-894). Shambhala Publications. Kindle Edition.