Step 1: Locate and copy the MT4 EA or custom indicator file(s) you downloaded previously to your computer.
Step 2: On your MT4 platform, click the ‘File’ tab in the main menu and then click ‘Open Data Folder’.
Step 3: Click the MQL4 folder and then ‘Experts’ or ‘Indicators’ according to your preference. Next, drag and drop your EA or custom indicator file(s) into this folder.
Step 4: Restart the platform.