Our team created instructions that will help you to set up your Instagram developer client. In the end of the process you'll get Client ID and Client Secret that are required by InstaFox app to access to Instagram API. At first, go to instagram.com, login to your Instagram account and go to www.instagram.com/developer/
You can see "Manage Clients" link on the top right, go to clients manage page and then click "Register a New Client" button. It will look like below.
Then please carefully follow instructions on this page to fill all proposed fields. Please choose URL of your site as Website URL and URL of your website plus "/instafox/redirect/" in the end as Valid redirect URIs (e.g. http://myphpfoxsite.com/instafox/redirect/). It is possible that Instagram will require you to describe your application, simply enter "Integrate my phpFox website with Instagram" or something similar to that.
Also if you use the www version of your site, you need to enter with www, otherwise Instagram will not validate URL.
If you did everything right, you will be redirected to Edit Client page. Now your app is created, you can copy-paste Client ID and Client Secret to your AdminCP (http://myphpfoxsite.com/admincp/app/?id=InstaFox).
Nevertheless your app is still in Sandbox mode. You will be able to choose up to 20 users allowed to access your app in sandbox mode in Sandbox tab, but you'll have to go live to make your members able to use functionality of Instagram plugin. To do that, go to permissions tab and request "basic" permissions and submit your app for review. Instagram may require you to show a screencast of the functionality of the app. You may perform simple screen recording and show Instagram plugin on your profile (your account is enabled in Sandbox mode by default).
When your app will pass review you will be able to change client status from Sandbox to Live. From this moment your Instagram app will be accessible for all your users.