Regarding posting private message in facebook

A. Log into your facebook account.

1.Scroll down, click on the notifications, this will show you the names and the photo icons on the people linked to your facebook account.

2.Click on the name of the person that you want to send a message to.

3.Then you will see the name, their image if uploaded and then two icons 'Follow and Messages'

4.Click on the messages icon. A pop up window opens where in you can type your message. type and then send, it will be private.

B.The other way is go to your homepage, select on the messages link. This opens up a blank message. Then you proceed like how to do a regular google e mail. Start filling the name of the person and then type your message and click send. This will be like a private message.

First of all my sincere suggestion to you is don't send personal messages to anyone through the social network. The confidentiality here is not very reliable. So I feel it is better to send the message by email. That is the safest way.
If you still feel you want to send through facebook you can go the profile page of the person whom you want to send the message. On the top, there will be a column called message. Click on that and message page will open. Then you can type the message and it will go to the particular person.

Go to account / profile page --> Setting and Privacy --> privacy
Under privacy there are option to control your future and past posts, pages other lists you follow.
Simple other way is to use facebook messenger to send message. It is secured and only two of you can see it.

1. Log in to your Facebook account.
2. See the list of your friends.
3. Click on the name of the friend to whom you want to send a personal message.
4. Your friend's profile page would appear.
5. In the upper portion of the right-hand side of your friend's profile page, a 'message' button would appear. Click that button and send a message to him/her.
6. However, if your friend has already declined any personal message, you won't be able to send a message to him/her.

It is a very simple task. If you are using Facebook through phone, by a browser, then you can't directly send a message on Android phones nowadays. Facebook messenger ad keeps popping up, unless you download it.
So download the messenger app of Facebook from Play store. Complete the login procedures. When done, you will have to search the particular friend's name and tap on his profile. You will enter a chat box and done. Drop your message there. Facebook messenger is very useful because it notifies you every time someone accepts your friend request, allowing you to be in touch with a person as soon as he becomes your friend. It has many many awesome features which you will enjoy.

But if you are using Facebook on PC, no need of any such procedures. On the blue bar that appears above your home screen, you will find a message symbol. You can go there and send a message if a friend is online. Else go to that friend's profile and tap on the message icon.

By the way, right when you sign up for Facebook, all the information about icons are readily shown to you. Facebook is extremely used friendly. If you find it difficult go to Facebook help centre. You can enter it by scrolling through Facebook's settings menu or just type "Facebook Help" in Google.

Sending instant private messages in Facebook to a particular person is done through the following ways, after you are logged in to your account.

1. You visit the profile page of a person
2. Below their profile image, you get three options, Add Friend, follow, Message, More
3. If the individual is already in your friend list, even then you get the option to send a message in this way, which he/she will get to see when they open their Facebook Account.
4. If he/she is not in your friend list, even then you can send a message this way, although the messenger settings of that individual will decide, how your message will appear to them.
5. you can now install Facebook messenger as an android app on your smartphone, where you can send messages, video call, and make voice call to any profile you want.
6. But the voice calling and video functionalities will only be available, if that individual and you are connected to each other as friends.
7. When two people are not connected as friends, the messages will get filtered as other messages, and the recipient will only come to know about them, if they keep their settings that way.
8. Once they accept your friend request, all the above-said functionalities will get enabled.