Before the service - all introverts should equip themselves with a laminated A5 size card. The card reads "Please do not bother me before the service. I am talking to Someone more important than either of us."
During the "welcome" - any introverted newcomer picked out by name and asked to introduce themselves is allowed to walk straight out.
At any time during the service, any ad-hoc response requested by the worship leader - as it may be, questions aimed directly at the introvert such as "isn't life great" or "what's God done for you this week?" may be met with a Hard Stare.
If you are requested to discuss God's recent blessings with the nearest stranger, remember that the weather is one of God's blessings too.
Ministry of the Word
Responsive reading of Psalms is perfectly acceptable. "Guess the next verse" games where individuals are picked out randomly to give answers are not.
Under the Geneva Convention, it is illegal for a preacher to follow a leading question such as "and I'm sure we'd all like to think we follow these rules in our own households - wouldn't we?" with direct eye contact.
When asked to break up into small groups to discuss "how we experience God's purposes in our own lives" it is acceptable to look at your feet throughout.
Asking people to write down prayers on pieces of paper for summary by the person offering prayers is fine. Going round person-by-person for a request each is going too far.
During the sharing of the Peace, adopting the foetal position on the floor risks attracting more attention than it should in civilised society. Staying locked in a "praying" position may maintain your personal space, although it may instead just attract extraverts to join you / lay hands on you. Answering a "call of nature" at this point every week may lead to someone calling you out the front for healing of your weak bladder. The best bet is to stand rigidly in a spot against a wall, where you cannot be hugged, with a vacant gaze.
After the service
Visitors and newcomers be warned. The extraverts have made the definition of "not ignoring anyone" far more intrusive than the quiet nod or word of welcome that lets you get on with drinking your coffee in peace. If you are in an old church, take the opportunity to get a good look at every single memorial and piece of stained glass. If in a new one, feign an interest in the notice sheet. If questioned, you only have to give name, former denomination and a vague clue to your occupation.