When you are using MH Magazine WordPress Theme, it's up to you if you want to display one classic sidebar, two sidebars or even no sidebars at all. You can manage the sidebars from your WordPress dashboard under "Appearance => Customize => Layout Options". There you will find an option "Sidebars" where you can just select how many sidebars you want to display on your site.
Enabling a second sidebar #
After you have activated a second sidebar in MH Magazine, the two sidebars will be displayed next to each other on your site by default (unless you haven't placed any widgets in the "Sidebar" and/or "Sidebar 2" widget location). You can also place one sidebar on the left and the other sidebar on the right to have your content in the middle between the two sidebars. To do this, please just change the option "Position of default Sidebar" as you like.
Responsive layout with two sidebars enabled #
When you have enabled the second sidebar, the maximum width of your site will automatically increase from 980px to 1300px. This is necessary to ensure that there is enough space available for the second sidebar. Please keep in mind that the theme is fully responsive (it will automatically adapt depending on your screen resolution) and that sidebars will automatically float to the bottom of your site on smaller screen resolutions or mobile devices.