Update README.md: add How to use section and fix section links

Author: replydev

README.md

@@ -1,3 +1,4 @@
+
 # cotp - command line totp authenticator
 
 I believe that security is of paramount importance, especially in this digital world. I created cotp because I needed a minimalist, secure, desktop accessible software to manage my two-factor authentication codes.
@@ -7,7 +8,7 @@ cotp is written with simplicity in mind, it relies on only one database file, en
 
 The interface is quite minimalist and intuitive, by typing `cotp -h` you can see all the program features.
 
-You can also import backup made by [Aegis](https://github.com/beemdevelopment/Aegis) and [andOTP](https://github.com/andOTP/andOTP) Authenticators, but backup compatibility is growing (check [planned features](##planned-features))
+You can also import backup made by [Aegis](https://github.com/beemdevelopment/Aegis) and [andOTP](https://github.com/andOTP/andOTP) Authenticators, but backup compatibility is growing (check [planned features](#planned-features))
 
 ## Installation
 
@@ -29,10 +30,40 @@ Then choose how you want to proceed
 	makepkg -si
 	```
 ### Other distributions
-You can use prebuilt binaries or [build cotp](##building) yourself
+You can use prebuilt binaries or [build cotp](#building) yourself
 Go to [releases page](https://github.com/replydev/cotp/releases/) and get the latest version.
 
-
+## How to use
+If you are familiar with the command line interface using cotp will not be a problem.
+As i said before, if you type `cotp -h` you get some instruction on how to use cotp utilities.
+For example, the version 0.0.9 prints out this help screen:
+```
+cotp v0.0.9
+written by @replydev
+
+ARGUMENTS:
+-a,--add <secret> <issuer> <label>       | Add a new OTP code
+-r,--remove <secret> <issuer> <label>    | Remove an OTP code
+-e,--edit <id> <secret> <issuer> <label> | Edit an OTP code
+-i,--import aegis,andotp <filename>      | Import a backup from a given application
+-ex,--export                             | Export the entire database in a plaintext json format
+-j,--json                                | Print results in json format
+-h,--help                                | Print this help
+```
+Note that in the `--edit` command if you type . instead of argument you are specifying not to modify that specific argument.
+### Example:
+#### Before:
+|index|secret|issuer|label|
+|--|--|--|--|
+|3|NB2HI4DTHIXS653XO4XHS33VOR2WEZJOMNXW2L3XMF2GG2B7OY6WIULXGR3TSV3HLBRVC | Rick | Asley |
+#### Command:
+
+    cotp -e 3 . . cotp
+
+#### After:
+|index|secret|issuer|label|
+|--|--|--|--|
+|3|NB2HI4DTHIXS653XO4XHS33VOR2WEZJOMNXW2L3XMF2GG2B7OY6WIULXGR3TSV3HLBRVC | Rick | **cotp** |
 ## Building
 First of all install the rust toolchain:
 
@@ -47,17 +78,15 @@ You will find the compiled binary in **target/release** folder
 
 ## Planned features
 
- - Reduce binary size and improve compilation speed by removing useless dependencies.
- - Use argon2id13 for key derivation
- - Backup compatibility with:
+ - [x] Reduce binary size and improve compilation speed by removing useless dependencies.
+ - [ ] Use argon2id13 for key derivation
+ - [ ] Backup compatibility with:
 	 - [x] Aegis
 	 - [x] andOTP
 	 - [ ] Authy
 	 - [ ] Google Authenticator
 	 - [ ] FreeOTP
- - Graphical User Interface 
+ - [ ] Graphical User Interface 
 
 ## Contribution
 I created this project for my own needs, but I would be happy if this little program is useful to someone else, and I gratefully accept any contributions.
-  
-