Update README.md

Author: Mohammad Khoddam

README.md

@@ -6,3 +6,28 @@ The Tetris game written in Assembly 8086 language
 Tetris (Тетрис) is a tile-matching video game created by Russian software engineer Alexey Pajitnov in 1984 for the Electronika 60 computer. 
 
 In this project I have rewritten this nostalgic game in Assembly 8086 language.
+
+## How to run
+
+1- Compile the code via [EMU8086](https://emu8086-microprocessor-emulator.en.softonic.com/download) to produce .exe file (You can skip this step by using the existing .exe file in Repository's Releases section)
+
+2- Run .exe executable file in [DOSBox](https://www.dosbox.com/download.php?main=1) by using below commands:
+```
+mount [DriveName] [AbsolutePathToEXEFile]
+[DriveName]:\
+[EXEFile].exe
+
+```
+Example:
+```
+mount C C:\emu8086
+C:\
+cd MYBUILD
+tetris.exe
+```
+
+3- Enjoy the game.
+
+## Screenshots
+
+![Screenshot 2021-04-30 104009](https://user-images.githubusercontent.com/44812192/116668176-4f060700-a9b2-11eb-8096-c6ef130c8436.png)