Update README.md

README.md

@@ -1,7 +1,9 @@
 txtool is made to help you for easly pentesting in termux,  
 build on termux and only available for termux.  
 
-# installation steps: 
+Installation steps: 
+===
+* make sure Termux already installed on your device, you can get Termux on [Playstore](https://play.google.com/store/apps/details?id=com.termux) or [F-Droid](https://f-droid.org/packages/com.termux/)
 * require python version 2.x  
 
 ```
@@ -11,7 +13,25 @@ $ apt install python2
 $ ./install.py 
 $ txtool
 ```
-
+
+How to contribute ?
+===
+if you are interesting with this project, you are welcome to open pull request
+* fork this repository
+* create new branch on your forked repository
+* push your commit to new branch on your forked repository
+* finally open new pull request
+
+Know problem ?
+===
+* for ssh backdoor access, txtool used `paramiko` python library that required `PyNacl`
+if you have an error installing PyNacl, follow my steps:
+```
+$ apt-get install --assume-yes libsodium libsodium-dev
+$ SODIUM_INSTALL=system pip2 install pynacl
+```
+or you have another error, please submit a new issue.
+
 # Screenshot  
 ![Screenshot](https://raw.githubusercontent.com/kuburan/txtool/master/screenshot/Screenshot_a.png)  
 ![Screenshot](https://raw.githubusercontent.com/kuburan/txtool/master/screenshot/Screenshot_b.png)