Modify Linux/MacOS installation instructions for OSC to use a virtual environment (#180)

* Change instructions to create virtual environment

* Change warning to notify about VENV

* Rename image to resolve missing file issue

* Modify img link to reflect filename change (oops)

* Specify alias differences for Python on Linux

Author: grunt22fox

docs/osc.md

@@ -71,24 +71,32 @@ If you get a User Account Control pop-up that asks whether or not you would like
 
 ::: warning
 
-You will need Python 3 installed in order to use OSCDL on these platforms.
+You will need Python 3 installed in order to use OSCDL on these platforms. Please note that on certain distros, Python 3 may use either `python` or `python3` as an alias, please be aware of this for Step 6. You will also create a virtual environment to isolate OSCDL and its dependencies from your base Python installation.
 
 :::
 
-1. Download the source code for OSCDL, either the `.zip` or the `.tar.gz`.
+1. Download the source code for OSCDL, either the `.zip` or the `.tar.gz`. Optionally, you can instead run `git clone https://github.com/dhtdht020/osc-dl.git` in the directory you would like to use OSCDL in.
 
     ![](/images/osc/source-code-download-OSCDL.png)
 
-1. Extract the archive to a location on your computer that you would like to use OSCDL in.
-1. Open the location of the extracted files in a terminal and run the command `pip install -r requirements.txt`. This will download Python packages needed to run OSCDL.
+1. If you chose to download the source code, extract the archive to a location on your computer that you would like to use OSCDL in.
+1. Open the location of the extracted files in a terminal and run the command `python3 -m venv venv` to create a virtual environment. Note that, if you receive a message that `ensurepip` is not available, you must install the `python3-venv` package for your distribution. Python may provide a command for you to use to accomplish this.
+
+    ![](/images/osc/create-virtual-environment.png)
+
+1. Run the command `source venv/bin/activate` to activate the virtual environment.
+
+    ![](/images/osc/activate-virtual-environment.png)
+
+1. Run the command `pip install -r requirements.txt`. This will download Python packages needed to run OSCDL.
 
     ![](/images/osc/satisfy-requirements-OSCDL.png)
 
-1. Run the command `python3 oscdl.py`. This will open the program. Optionally, you can also create a desktop shortcut that runs this command for easier access.
+1. Run the command `python3 oscdl.py`. This will open the program. If you choose to keep the terminal open, you can use `deactivate` to exit the virtual environment. Additionally note that you must run `source venv/bin/activate` in the directory where OSCDL was extracted every time you open a new terminal. This is in order to load the dependencies needed to run OSCDL.
 
     ![](/images/osc/run-OSCDL-terminal.png)
 
-1. Find an application that you would like to get, and press the Download button. Alternatively, you can send the app directly to your Wii (this requires that your computer and Wii be on the same network).
+1. Once OSCDL is open, find an application that you would like to get, and press the Download button. Alternatively, you can send the app directly to your Wii (this requires that your computer and Wii be on the same network).
 
     ![](/images/osc/app-download-OSCDL-linux.png)