RWD major challenge these days is testing your content on all Mobile browsers and provide a seamless user experience. The desktop side of RWD that will fit and scale inside a desktop browser is relatively easy as there are no more that 3-5 different types of browsers.
On the mobile side, its entirely a different story as there are 10 + mobile browsers out there in the wild (default + installed). The user might view the website appropriately in the desktop version, but when the same website is viewed through his mobile phone, it’ll look odd and janky. What you need is a “device” plan of attack. Know which device classes you intend to support before you start to code and create content.
Have both your lowest common denominator devices and your high-end device designs before you begin to code. Try to visualize a way to create both versions from one code base and Test on different mobile devices from the beginning to the end to ensure that your incremental work will display correctly in the intended devices. Its good to have a small design lab where you can set up all these mobile devices and test your content. Designing and supporting multiple mobile displays takes time and patience. Responsive Design includes the use of CSS3 Media Queries, which is supported by almost all modern browsers and it reactively determines the screen size of a device and then renders the content appropriately on the screen layout. With a set of media queries, you will be able to display different layouts on different devices.
After successfully making your website responsive, you need to perform responsive test online on multiple devices like Mobile Phones, Tablets, Laptops, Desktops to ensure the responsive web design and that content and images are adapting themselves as per the screen size in which they are being viewed on. A good plan is half of your success. This is why planning ahead every little part of your responsive website design is crucial.