HELLO FOLKS!
Greetings from @drskhan90

As a newcomer to steemit, I understand the difficulties you must be facing to understand steemit platform. Its better than other social networking platforms you have been using until now and that's why its a bit difficult to understand few technical parts of steemit. But I promise, you will learn it very fast and will keep learning always.

Lets Get Started!

FIRST THING FIRST

1. Store your password /key in safe place (read physical locker).

Do not store it in your email (emails can be hacked).
Get a printed copy of all the three keys (posting key, Active Key and Owner/Master key) and keep it in safe place and out of reach of children and even adults because later one can do more harm. The reason being, once you lost your keys, there is no other way possible to recover your steemit account. And you will lose your millions of dollars which you might mint here.

2. WHICH KEY TO USE WHEN

POSTING KEY = as name suggests, use it to login and post. If you ever consider using any bot services for upvoting , it is this key they need from you. you can share this key for availing the bot services after a little research but at your own risk. PUBLIC POSTING KEY starts with 'S' and PRIVATE POSTING KEY starts with '5'. They will ask you for private posting key which is hidden by default until you click on "SHOW PRIVATE KEY". you can have a look at your keys under WALLET > PERMISSIONS.

ACTIVE KEY = the active key is used to make transfers and place orders in the internal market i.e whenever you need
to send money out of your steemit account you will need this key and use it only for this purpose.
Never ever share this key with anyone.

MASTER KEY = the key you generate while signing up is your Owner/Master key. DO NOT USE MASTER/OWNER KEY FOR LOGIN PURPOSES. Use it only when required. It is required to change all the other keys. Which you might want to consider when god forbid, your account gets stolen or hacked. Never ever share this key with anyone.

3. INTRODUCTION (#INTRODUCEYOURSELF)

Before jumping into writing anything and everything, please introduce yourself to the community. We here at steemit love to see new members joining in, and therefore we greet them with a very warm welcome. Its a convention to display your name/username and date of joining on a placard . you may choose your own style. But make sure to add a photo of yours so that its easy for us to not consider you another bot.
Write about you whatever you want to. Its better to go through some other folks #introduceyourself post to get a glimpse of how to write but maintain your uniqueness.

4. Be Patient and Be Healthy

Don't get frustrated by looking at the payouts of trending posts. They have earned it through dedication and patience. Learn from them. Go through their posts and analyse how they did it.

5. SOCIALIZE. WELCOME NEW COMERS . MAKE FRIENDS.

Remeber. Steemit is a community of bloggers. Greet and welcome the new steemians on #introduceyourself . Its these new friends you make here will follow you. Comment on their post in a way that make them feel that you are actually interested in them. Do not post vote4vote or follow4follow. If you engage with them truly, they will definitely vote for you and follow you. More followers means more number of people getting your feeds (read blog). Follow them as well and help them evolve by upvoting their posts.

6. REWARDS : two types

AUTHOR REWARDS (75% of the total payout) :

Whatever you write or post (even as comments or reply) if gets upvotes results in author rewards for you which is 75% of the total payout, which follows with a "$" sign. You will get it after 7 days . It changes with time as the price of STEEM changes regularly. So dont worry if it changes little bit or drastically.

CURATION REWARDS (25% of the total payout) :

It is the share of all the curators ( read voters) who have voted on a post. Suppose on a post of someone you voted , gets a total of $100 as payout. After 7 days $75 will go to the author of the post . $25 will be shared between all the voters. Now here comes the role of timing and Your STEEM POWER . Details will be shared on a separate post explaining how timing and steem power plays a role in curation rewards. simply put wait atleast 15 minutes before voting if not 30 minutes. more steem power means more curation rewards for you from that 25% share.

7. NUMBER OF UPVOTES YOU CAN DO

Just like facebook, where you can like millions of stuffs, here on steemit you can do that too. BUT HERE IS A TRICK. There is a term called VOTING POWER (VP) which decreases as you keep on voting, take it, as 2% for every upvotes. maximum is 100% when your VP is full. But if you take a break it will start filling to 100%. So be nice with everyone but keep your VP reserved for some good posts or comments because they deserve your votes more than any other random thing you come across.

8. STOP FOLLOWING THE TREND. SEARCH AND MAKE ONE.

DO NOT FOLLOW THE TREND and keep voting the trending posts. Curation rewards will be much higher if you find a diamond before its already a trend. so keep looking for it in the "new" posts . if you find one, keep a watch on it and ideally, just after 30 minutes (if the post has not garnered a lot of votes already) upvote it. RESTEEM comes to play a great role here. If you resteem this diamond and it becomes a "trending" or "hot" you will get awesome curation rewards because you were amongst the early voters.

9. WHAT TO POST AND WHAT NOT TO

Post whatever you like. But NO COPY & PASTE. If really necessary to copy & paste, then quote the creator/source and if possible take their due permissions. Because Steemians are smart enough to recognize originals and kind enough to appreciate it.

10. REPUTATIONS

Wondering what the no is (25 when you start on steemit) after your username? Its your reputations which is by default 25 but increases when you interact in communityand get upvotes. contrary to that it may decrease if you get flagged (read reported). Its increase or decrease depends upon who upvotes you(whether a whale, shark or a minnow) or flags you respectively. Reputation helps you in reaching out to mass as many a times people look at your reputations before reading your post. So keep it up and keep it safe.

Much more are there to share with you. Follow for more updates . Upvote, comment, criticize, resteem.

LOVE.PEACE.

THANKS A LOT FOR READING.
Thanks @exyle for info on different types of keys.