You can do this by installing multiple trading terminals on the same computer.
For opening multiple MetaTrader accounts on the same computer simultaneously, you'll need to have installed multiple terminals on the same computer.
Just repeat the same procedure as if you would install a single MT4/MT5 terminal, except that you'll need to choose a different location upon installation.
Change the installation destination folder
When you run the MT4 installation, it will give you an option to change the installation destination folder.
Look for the “Settings” button which will become accessible once you select the “Yes, I agree …” box.
When you click the “Settings” button, you’ll get to the next step where you are allowed to change the MT4 installation destination folder.
Normally, by default, the MT4 installer sets an installation folder to something like C:\Program Files\Metatrader 4\ which is completely fine for the first installation.
However, when you install the 2nd, 3rd, or any other terminals, you need to change this location to a unique folder name that does not exist yet.
We would suggest naming folders with different numbers at the end:
C:\Program Files\Metatrader 4-1\
C:\Program Files\Metatrader 4-2\
C:\Program Files\Metatrader 4-3\
The different numbering at the end of the folder name will help you identify terminals and keep all installation files in different folders.
Of course, you can give folders whatever name you want, but make sure that each name is unique.