To install AutoIt first download the AutoIt exe file from the below location.

Click here to Download AutoIt exe file

About AutoIT : AutoIt v3 is a freeware BASIC-like scripting language designed for automating the Windows GUI and general scripting. Please refer AutoIt for more details

Step 1:
Click on download at AutoIt Full Installation

Step 2:
Click on AutoIt Exe file.

Step 3:
It will display the setup wizard screen and asks you to click on Next button. It will also display the version of AutoIt that your installing.

Click on Next button to proceed for installation

Step 4:
It will display License Agreement screen. Click on 'I Agree Button' to accept the terms of the agreement if you want to continue the installation.

Step 5:
If you are running on 64-bit Operating system, it will ask you to choose from the below two options.

1. Use native x64 tools by default
2. Use x86 tools by default (recommended for compatibility)

Choose the recommended one and click on 'Next' button

Step 6:
It will Ask to select a default option when you 'double click' on the *.au3 (AutoIt file extension) files. It will display with two options

1. Run the Script
2. Edit the Script

Choose which ever you are comfortable with and click on 'Next' button

Step 7:
Next it will Ask you to choose what type of installation you want. It will also show you the amount of space that is required for the AutoIt.

Choose all and click on 'Next' button, which will download all the AutoIt examples which will definitely help you writing the scripts

Step 8:
It will ask you to choose the location to install AutoIt. By default it will take the destination folder as Program files. If you wish to change, you can change the destination folder.

Click on 'Install' button to complete the installation

It will display a message as, 'Please wait.. installation is in progress'.
After that it will display message as "AutoIt vX.00 has been installed successfully on your computer".

After installing successfully, please go the folder where the AutoIt is installed. In that folder, you can see the folder as 'Examples' where you can find many examples which will actually help you in understanding autoIt scripts.