Most of these tips apply to an introvert's travels anywhere in the world - at least the densely populated parts of the world. That said, India - particularly urban India - presents a daunting degree of challenge.
This is because Indians, to generalize a bit, love sensory stimulation, and are used to a vibrant environment full of colors, sounds, and scents. There's an old story about an Indian man clinging to a cliff. At the cliff's edge and within reach of the rock to which the man clings, there are two things. One is a sturdy loop of gnarly tree root, and the other is a fragrant flower. As the story goes, the man snatches away the flower and blissfully plummets to his demise while enjoying the flower's scent the entire way down. It's probably not a true story, but hopefully it illustrates that it's not just my opinion that Indian tolerance for sensory stimulation is above average, and that means it can be an especially draining place for introverts.
5.) Pace yourself / build quiet time into the itinerary: Spending a full day among the bustling masses of an Indian city can be exhausting for an introvert.
For the longest time, I was under the impression that I had a disproportionately high likelihood of going hypoglycemic (i.e. using up my glucose and getting cranky.) And maybe there's some truth to it, but I know I'm a lot easier to get along with on a nature trek having skipped lunch than I am if I skip lunch touring a city. While I need to recharge my calories periodically, I think I need to sit down in a relatively quiet place even more.
One may want to keep an eye open for restaurants and cafes that look like good refuges as one tours, because it's not always easy to find suitable places on the internet. One may find that the cafe one planned to rest up at, the one with fantastic ratings, also has no seating and / or is a beehive of mad activity.
4.) Be aware of the locations that will bring an over-abundance of random visitors: One will find, at certain times and places, that random people will come up to: a.) take a picture with you; b.) have their child's picture taken with you; or, c.) to practice their English (or relevant language.) It's fantastic the first few times in a day.
This phenomena is by no means unique to India. China is legendary for having parents who want their child's picture taken with a foreigner - and the more foreign you look (e.g. if you are a six-foot tall blonde woman) the more of these visits one is likely to experience.
As I said, even as a hardcore introvert, I enjoy these interactions in regulated doses. That's part of what one seeks from travel, interacting with locals who aren't in the tourism trade. For example, in Phnom Penh, Cambodia, I found these chats ( a few times a day, max) endearing and insightful.
It's a matter of scale. The shear density of people in India can result in the situation getting out of hand. I've actually had lines form as though I was some sort of visiting dignitary. As in most countries, the average person isn't super comfortable approaching strangers. However, once people see that some bold individual succeeded, they become emboldened. Eventually, all these interactions can become too much to maintain an energy level conducive to sightseeing.
Unlike sensory bombardment, this is one issue that is actually lessened in the heart of a big city. In Mumbai, Kolkata, and Bangalore, one doesn't experience this as much. (Delhi, too. Though in Delhi one will frequently be approached, but by professional con artists. Sorry, Delhi is my least favorite part of India by a large margin.) These big cities see foreigners constantly. One will still be approached on occasion: a.) if one is in a neighborhood distant from the heart of the city where the people don't see many foreigners, or b.) during festivals / holidays when many people come in from the villages. Villagers hit some of the same tourist spots as do foreigners.
I've found that the largest numbers of strangers approach in smaller cities like Aurangabad, where they don't have a ton of expats and foreign companies compared to Bangalore or Mumbai, nor do many of the small to medium-sized cities attract massive numbers of foreign tourists in the way that a few small cities like Rishikesh and McLeod Ganj do.
Ultimately, one just has to have a polite exit strategy, which may feel a bit rude. Which brings me to...
3.) Avoiding being overwhelmed by touts: Unlike the pleasant, but potentially draining, interaction with locals, touts are just annoying. Like other places I've visited that have high rates of poverty and thus high rates of desperation, including parts of Latin America and China, the touts in India can be downright clingy, and will follow one for miles buzzing in one's ear if one doesn't handle the situation properly.
Introverts are often self-conscious of the fact that they can seem rude when they are turned inward in the presence of others. So, one may be tempted to keep saying "No thanks" to the tout who has followed you for two blocks. However, as long as one continues to acknowledge a tout, one gives hope - no matter how explicitly your words may be saying no. This thread of hope is what leads to the relentless behavior. After I discovered this, I began to say "no thank you" only once, and then to ignore the tout like he didn't exist. It saved us both wasted effort and traveling got much easier. Two or three steps of completely ignoring a tout will achieve more than two miles of trying to explain why you neither want or need what he's selling.
2.) Be careful where your vision goes if you zone out into your own head: The subject of eye contact comes up in almost every post I do on introversion. Probably because I've just recently become aware of the degree to which I under employ eye contact, and also because India has an unusual norm for eye contact. In most countries, there's something like a one-second rule. One makes eye contact with strangers for around a second before averting one's eyes. One may look back, but one doesn't sustain eye contact endlessly. I don't want to make one think that most Indians will stare at you ceaselessly, but a few will - particularly those who don't see or interact with foreigners often.
My point with this item is that when one zones out and stares off into the distance, one can create a number of problems for oneself, including: a.) convincing touts you are interested in a product that you aren't, because it looks like you are staring right at it; b.) females may gain undesired attention from males, c.) males may gain unwanted attention from boyfriends or husbands.
1.) Beware of the importance of eye contact, but don't try to keep pace with those who lock eyes. Like traveling anywhere else, it's important to make brief eye contact for both sociability and security. However, if you try to keep up with those who can stare the paint off a pump-handle, your energy is going to drain quickly.
I should conclude by saying that traveling is nothing one should be anxious about as an introvert, and, furthermore, introversion can have its advantages. (Not the least of which is the fact that if one has acclimatized to feeling oneself the odd man out, one is well placed to plop down in different culture.)
