If you want to edit a certain module , you click edit and you will be redirected to the module edit page.
We will take as an example the latest products module:
1. Click edit on latest module.
2. Now you will probably view few rows if you allready added the module to layouts(lets concentrate on adding modules though), so lets say that you want to add the module latest to the information pages.
3. Below the table is a button called add module . Press that button and another row will appear in the table with settings that needs to be made:
3.1 The first column is Limit which represents the number of products you want to display in that module.
3.2 The second is Image sizes made by 2 cases , the first one is for image width and the second one for image height. Why set this? Opencart uses a script for creating thumbnails because when you upload the product image , you dont pay attention to its size and because you need the image in different sizes on different cases. So the size you set there is the size the product image will be in that module.
3.3 This is the layout. Which basicaly means what page or group of pages the module will apear on. So basicaly if you want your latest module to appear in the information pages you select the layout information.
Note: If you want your module to appear in all pages on your website , you need to add a module for each layout and make the settings for every layout.
3.4 Here we have the position: By default there are 4 available positions :
3.4.1 Column left - will display the module on the selected layout on the left column;
3.4.2 Column right - will display the module on the selected layout on the right column;
3.4.3 Content top and content bottom will display the module on the selected layout on the middle , above or below the content. On home page layout , does not matter if you added the to content top or bottom (maybe only the order) because on homepage there is no content , there are only modules if you add them. But for example , on product page , there we have content , the product description , so the content top will apear above the product desc and the content bottom , below it.
3.5 Here is the status. If enabled , the module will apear , if disable , the module wont appear.
4.6 The last one is sort order. Which sorts the modules apearance within a layout and position.
Example : On the homepage layout , on the right column you've added 3 modules. Youve added the account module with the sort order 2 , the featured module with sort order 0 and the latest module with the sort order 1. o on the right column the module will apear in this order: Feature - Latest - Account.