Setting Up MAMP 4.2.1 on Mac OSX Sierra

MAMP stands for MyApache–MySQL–PHP and is used to set up a personal local computer to behave and act as a web server. MAMP is the MacIntosh version (Apache) and LAMP (Linux) is the Windows version.
I will only be walking through the steps of installing MAMP since that is the platform I use. The steps are basically the same on any PC using LAMP.
Also, this guide is for the FREE version of MAMP. I will post the MAMP PRO version in a future tutorial. MAMP PRO will cost US$59.00, or US$29.00 if you own MAMP PRO 3.0 and want to upgrade to MAMP PRO 4.0.
Right now we just want to get a local server development environment up and running, so let’s begin by installing MAMP 4.0, the FREE version.

Download & Install MAMP

In your web browser, navigate to https://www.mamp.info/ and download the free version of MAMP.

Once you click on ‘DOWNLOAD,’ you will be taken to a new window screen that will automatically detect the computer you are on and the platform you are using. In our case, the MAC OSX selection will be highlighted.

You will notice in the image above, the right sidebar of the download page offers several versions of PHP to download. These versions allow you to set up your local server to match the version of PHP that your webhost provider uses to host your site. We will discuss these options in a moment.

For now, let’s download MAMP & MAMP PRO 4.2.1 (Mac OS X) by clicking the Download button. MAMP will automatically download the installer package to the location you have your browser set to save downloads.
Navigate to the directory where the installer package has been saved and double-click the installer package to begin the installation. MAMP will install in your Applications directory.

After Installing MAMP

MAMP will install two (2) directories in the Applications directory: (1) MAMP, and; (2) MAMP PRO. All the files/folders/directories we will access and/or add will be in the MAMP directory, which is the FREE version of MAMP.
When opening the MAMP directory, you will see the folder structure as shown in the image below.

MAMP & PHP Versions

In the free version of MAMP you can select between two(2) different versions of PHP at a time from the settings option window by selecting the PHP tab. The standard version of PHP for MAMP is 7.0.20 and the additional option is 7.1.6.
Chances are that your webhost service provider is not running either of these versions and more likely running version 5.x.x. For example, godaddy.com webhosting uses versions 5.2 thru 5.6 (NOTE: If you are going to be setting up a WordPress site, it is strongly recommended to use the latest version of PHP – well, at least version 7 according to wordpress.org).
Determining the Version of PHP You Need to Employ Locally
The good news is you can download the version of PHP you need to run in MAMP in order to match the version your webhost service provider is using for your live production site. This is done by first checking with your webhost service provider and then downloading the version you need from MAMP ‘s download page. The available versions are located in the right sidebar (see Figure 2) at this URL https://www.mamp.info/en/downloads/.
Once you download the version you need to use, there are some steps you need to take in order to make this version one of the two (2) options mentioned in the previous paragraph.
** Need to find out how to actually accomplish this in MAMP 4.2 **