if among coworkers or other such people you know almost nothing about but are always mingling in work situations.. observe some traits .. not in a creepy sneaky way just a pic of a dog on their desk or every tuesday a few order out a pizza lunch type thing .. then simply small chit chats that are focused in those areas... oh i saw on news last night some dog food recall ... or hey a friend of mine said that new pizza joint is real good ...
if its a stranger in check out grocery line . find a goofy headlne on some gossip tabloid right there in the rack and comment on that..
an employee of one of ur frequent haunts u r always running into each other, refer back to a prior trip in that store and mention oh man those new chips u guys got in are yuuummmy... or wow i love those flower pots back there il remember them when i repot some of my plants
you can always bring up a subject in terms of needing advice or sugestions.. but dont make stuff up to do it . draw on current things really going on.. .. i got no clue what to get my nephew for his graduation .. any one have a good suggestion to get him.. or.. hey just letting you know passing the word, the hamburger helper ON SALE at grocery isnt ringing up sale price so just watch & make sure you dont get dupped.
once you can get to feel comportable in those sorts of impersonal/ personal interactions the rest will fall in to place as you build more common areas of interest and it will start to come more easily and naturally for you to do.