I am a newbie to rpg play by post. I want to play but don't know how.

  It's not exactly like experiencing a tabletop role playing game in person or by remote communication (social media). It does not have the immediate feedback that many people work off of in a social milieu. Which brings up the hardest challenge in Playing by Post, maintaining momentum so the game does not prematurely fade out.

Basically Play by Post is like playing via mail, be it: postal mail, email, or by RPG forum posts on a designated forum. You as a player write out your responses to the scenes written up by the Game Master. Sometimes the GM leaves things more open, or there is a more structured framework to constrain sensible responses (like starting in media res, in the middle of the action).

The best advice I can give you is consistency and self-forgiveness. Consistency is necessary to maintain momentum, given the potentially long delays between responses. Try to keep it with reasonable regularity, if you can. For example expect one response every 3 days, or once a week.

And the other is be prepared for it to fail due to reasons beyond your, or other participants', control. Life gets complicated and sometimes you have to deal with real emergencies or routines that suddenly piled up like a traffic jam. Remember, maintaining your life comes first, so don't beat yourself up for putting off communication for unexpected maintenance or emergencies. I've had to drop games I've run because of surgeries and illnesses, pause games because of work and or school reports, and let other players bow out gracefully for similar issues.

Communicate consistently while you can, and shrug when you cannot because "That's Life!" (Then follow up and explain when you can because it is courteous to do so.)

Hope that helps! 

I find electronic PBP is impossible to maintain indefinitely, the 'no break' format leans strongly to flurries of posts followed by burnout. I find a mix of PBP and live/VTT sessions can work well though. Another possibility might be some kind of 'season' structure with on and off periods, maybe as short as 1 week on 1 off. Or accept that a game will only run for a few months and structure around that.

I ran a pretty successful White Star RPG PBP last year using Discord, plus Roll20 as a resource for the VTT and to host maps, information etc.

Yeah, I've found it basically impossible as every PBP I've joined died out within a month.  The most frustrating was some guy who spent a month laying out all his guidelines for the game, along with detailed setting notes, repeated directives to all of us to check in daily etc., then he flaked out and ended the game two weeks in because he had "family issues." 

If you have literally no other options, you can try it, but I think even solo play is more rewarding.  I'm also not a big fan of gaming online in VTTs or whatever as it seems the technology is always failing someone.  If you have to game online, just use Zoom.

It can be fun, but only if you can adjust to how slow it is: what takes a few seconds at the table can takeweeks with PbP. Really. I've run games on a few forums and PbP is its own culture.

And like others have said, PbP games flicker out like candles in the wind. Expect it. Some players just enjoy making characters then vanish after the start. Some GMs are geeked about their game idea then disappear before or during the game. Then sometimes you get "That Guy™" in the group who burns everything to the ground.

I found, as a player, apply to as many games that interest you as possible. GMs only pick a few players and most games crash so the more apps you put in the better your chances of finding that rare gem of a game with a great group and a GM who refuses to quit running until the end is reached.

Also, don't always apply with the same fkn character in every game. Learn to write a simple character background that includes aspects of the GM's setting and try different types of characters, instead of constantly whipping out that same old Warlock you applied to a dozen other games with. On a lot of PbP forums the GMs are their own community, they get to know the boring and problematic players, and they select players who are creative, friendly and write well (well enough to understand walls of text are bullshit). Be willing to help the GM during recruitment/character-creation if you know the rules well and again be friendly. Some players love debating rules or the setting or how logical a situation is: DO NOT BE, OR PLAY, WITH THAT PERSON.

As a GM, I had to adjust to the speed. With a group of any size you can be waiting a week for everyone to respond to a post. So running multiple games isn't a bad idea because you can always find players and you'll be more active rather than constantly waiting. That said you'll still experience waiting and as a PbP GM you experiment by taking on more games until you hit a comfortable limit. A plus of PbP is GMs have more time to think about their reactions to the crazy shit players do.

On speed again: keep a fast pace. Slow posting is a PbP thing but if the GM is the slowest, players will get bored and punch-out. Be ready to make 2-3 posts a week to keep a scene going and if the players have accomplished everything they want in a scene, ask (out-of-character) if they're ready to move on. If yes, move on and sometimes don't ask, just move to the next scene. Most experienced PbP players will get notifications when the GM posts and they'll respond if you maintain a consistent, faster than normal pace. Even if it's a horrific railroad, they will respond, mostly because players are so used to GMs disappearing even riding a runaway train can be fun.

Also as either player or GM, if life throws you a curve and you can't post as often as required, LET THE GROUP KNOW. Just post "Hey guys my hands got really tired from masturbating so I won't be posting for a day or so". The group will understand and they'll appreciate the update and everyone can adjust for your absence. Respect travels.

Here's a great guide to PbP from somebody on Paizo's PF forum: https://paizo.com/threads/rzs2nr91?DHs-Guide-to-Play-By-Post-gaming

I've played in quite a few PbP games over the years. Some can last years, but most don't. Expect about half of the players to drop out of a game within the first month or two; that includes the GM.

I think your best option is to get involved in a game. If it doesn't work out, try again with another game. If you want to play as a GM, it's probably a good idea to play a game as a PC first.

PbP games are fantastic if one doesn't have enough boredom and frustration in their life. As someone that finds enough tedium and annoyance in the regular day to day grind, I long ago gave up supplementing it with PbP.

I think you would have much better luck asking this at a PbP site like http://rpol.net/
There you will find people that actually play or want to play, not just talk bad about it.

I've been running one for some mates for almost 15 years. I've found it's a practical way to keep your hand in, running for busy people spread across the country who otherwise would probably not find the time to game at all.

Depends on the format.
Play by Forum?
PBM is its own thing.

Play by forum you need some rules of posting laid out and a timeline. Otherwise it can easily devolve like others noted. But if structured then it can go on a long long long time. Someone has to keep a tight hold of the reigns and enforce players posting in some timely and at least half assed order.
 
PBM needs organization too. It worked really well when eGroups/YahooGroups was still around. I was in a Metamorphosis Alpha campaign for a while.