While I agree with what a lot of people have said so far in the thread, I would like to add one huge comment.
Don't go into a random walk-up encounter unprepared!
This is scary!
As most people have said, if you want to walk up to someone, whisper them to politely ask if they're receptive. If they are, the next step is absolutely pivotal!
PLAN AHEAD!!
I absolutely never go into a new encounter without something planned. My character is distant, guarded, and on her own, would likely never choose to interact with another. But there are so many ways to fix this! I've had her trip over someone. I've had her sneeze on someone. I've given her an obvious and minor injury to drive conflict and conversation. I've had her nearly vomit on someone!
Don't just walk up to someone and expect amazing roleplay to just magically happen! It might not! Set yourself up for success!! Think of something hilarious and cool that could happen to your character, or that your character could do to someone else.
Does your character think they are someone else?
Is your character racist against them?
Is your character doing something suspicious? (even if they aren't, phrase your words to add intrigue!)
Does your character think they are doing something suspicious?
There are so many ideas to spark off an amazing scene, and you will have people super interested to come back and roleplay with you again! Unless I'm roleplaying with someone whom I'm very comfortable with, I almost never play reactive.
I know some people greatly enjoy having nice, organic roleplay, and that's totally fine! That's not mutually exclusive with being prepared, as it were. Just think of a few little tidbits to add to the scene, and let everything else happen as it may! That's the stance I usually take anyway. I'll throw in a few ice breakers, stir the pot, then just let it boil!
If someone else is approaching you for walk-up, the burden is more upon them to have something interesting to say or do to draw the scene along, so don't fret about that, but if you are walking up to someone else, you should absolutely take five minutes to think of something to spark a scene first. It will be worth it! I promise you!
EDIT to comment: My closest and most valuable RP partner was gained from a simple, random poke. Don't let anyone tell you that walk up isn't fruitful (but certainly don't disbelieve them if they say it's hard!)
Don't go into a random walk-up encounter unprepared!
This is scary!
As most people have said, if you want to walk up to someone, whisper them to politely ask if they're receptive. If they are, the next step is absolutely pivotal!
PLAN AHEAD!!
I absolutely never go into a new encounter without something planned. My character is distant, guarded, and on her own, would likely never choose to interact with another. But there are so many ways to fix this! I've had her trip over someone. I've had her sneeze on someone. I've given her an obvious and minor injury to drive conflict and conversation. I've had her nearly vomit on someone!
Don't just walk up to someone and expect amazing roleplay to just magically happen! It might not! Set yourself up for success!! Think of something hilarious and cool that could happen to your character, or that your character could do to someone else.
Does your character think they are someone else?
Is your character racist against them?
Is your character doing something suspicious? (even if they aren't, phrase your words to add intrigue!)
Does your character think they are doing something suspicious?
There are so many ideas to spark off an amazing scene, and you will have people super interested to come back and roleplay with you again! Unless I'm roleplaying with someone whom I'm very comfortable with, I almost never play reactive.
I know some people greatly enjoy having nice, organic roleplay, and that's totally fine! That's not mutually exclusive with being prepared, as it were. Just think of a few little tidbits to add to the scene, and let everything else happen as it may! That's the stance I usually take anyway. I'll throw in a few ice breakers, stir the pot, then just let it boil!
If someone else is approaching you for walk-up, the burden is more upon them to have something interesting to say or do to draw the scene along, so don't fret about that, but if you are walking up to someone else, you should absolutely take five minutes to think of something to spark a scene first. It will be worth it! I promise you!
EDIT to comment: My closest and most valuable RP partner was gained from a simple, random poke. Don't let anyone tell you that walk up isn't fruitful (but certainly don't disbelieve them if they say it's hard!)