First off, I'm sorry guys because I have no idea how you should act or which norms may apply to you. This post is aimed mainly at women but you may be able to glean some useful ideas from it.
In India relationships are well defined across the family. Each person or relation has specific roles and guidelines for how to react to each other. There are norms and standards that are well known to desi's that they may not be able to explain to a pardesi. We (as pardesi's) are charting new territory. We're often not expected to behave as desi's, we're mostly forgiven when we don't know or live up to these standards and we're certainly not penalized for missing a formality.
Regardless of all of that, most pardesi's try to figure these standards out and do the best that they can. There's just so much that we don't know. From what I've seen, most pardesi women try to learn these things and then give up frustrated because no one in the family thinks they can understand or either they don't teach them the formalities because 'they're western.'
Whatever the reason, I thought I would help out with a little insight from my own learning. I'm too stubborn to give up and let anyone tell me I'm not Indian and don't need to worry about it.I know I'm not Indian, I don't want to be Indian but there is a certain satisfaction that comes from looking good in front of your family.
Now, I don't endorse or recommend any specific behavior, whether feminist or archaic, but if you want to fit in or gain family acceptance then you will need to take into account your spouses family history, how traditional or modern they are, etc. These tips apply to mostly traditional families but may also come in handy for more modern families.
Your Spouse's Parents
This one is easy. Greet them with the same respect you were taught as a child. Start out with formalities early in the relationship just as you would meeting anyone for the first time. Say Namaste to Hindu's, Sat Sri Akal to Sikhs, Asalaam Alaikum to Muslims, etc. Your spouse or soon to be spouse will be able to clarify exactly how you should greet them. It should not be expected for you to touch their knees/feet on the first meeting.
You can call them mummy and daddy ji or by other mom/dad type terms in their native language. Discuss this with your desi spouse before addressing them. Many Indian families welcome being called mummy and daddy and see it as a term of endearment and your acceptance of them. (The same applies to calling uncles and auntys by the terms uncle and aunty ji.)
Accept the snacks or chai that is offered to you. In some homes it's customary to refuse them the first time they are offered but you do not have to keep that formality. If you're unable to eat, respectfully decline and let them know why. If you don't want the snacks and chai it is okay to ask for something else like bottled water.
Many Indian FIL's will not sit in the same room as you even after you're married and living in the house. When you sit down, they will get up and leave the room. This is not rude behavior, it's their custom. In the event they stay in the room with you, then carry yourself like a lady and not a tramp. (i.e. don't sit gap-legged, lean over and let your boobs dangle, etc.)
Always dress conservatively. This has nothing to do with archaic values. It's showing that you respect their culture and that you're not some trashy westerner. It's no doubt they've seen western TV and none of it was good. Don't be the stereotype they're used to seeing. At least not in the beginning before you're settled into the family.
Your Spouse's Siblings
You should try to treat your spouses siblings like they are your siblings. His sister is your sister, etc. There will be times you don't get along and you don't agree on things and that's fine. Try to learn to live together anyway.
Don't hang out with opposite sex siblings as if they're your friend. You may get along with them great but it's still frowned upon to go sit in their rooms or be too friendly. Don't go into the room alone with any male family members of the opposite sex.
If you need anything and you cannot get it yourself, don't hesitate to ask your opposite sex sibling to get it for you. This helps strengthen bonds between the two of you.
Your Spouses Extended Family
Greet the extended family just as you would your spouses' parents the first time you met. It's not necessary to touch the feet/knees at this meeting. Be formal in the beginning until you know their habits and preferences. Accept food and drinks that are offered, even if you don't want them. Even if you only take small amounts it's considered acceptable.
If you don't understand everything they're saying it's okay. Ask your spouse for help as needed. The important part to your in-laws is that you make an effort. If your spouse can't help, smile and nod your head like you understand.
You can friend them on Facebook but don't post random craziness they won't understand. It doesn't take much to make a scandal. Many pardesi's choose to have a separate Facebook account just for their in-laws. This greatly reduces any problems you face from gossip, losing respect over something meaningless and random, etc.
Regardless of who you are around, remember your manners. Use the same ones you would with your family or for anyone in your culture. You don't have to stay somewhere you are uncomfortable, even if your spouse tries to tell you so. Your spouse knows how Indians should act in Indian culture but you have the advantage of "not knowing" those standards. If you mess them up or break a rule you are much more easily forgiven. Take advantage of being a pardesi who isn't supposed to know when you need to.
Don't sweat the small stuff. The worst they will do is ask you to do it their way the next time.
What are some tips you would share with other pardesi's about how to act around their in-laws?
How do you act with your spouses family?
Share with us what works and what doesn't in your family.