How to design for mobile-first: 7 essential tips

With mobile users now making up a major slice of internet traffic, understanding how to design for mobile-first isn’t just a nice-to-have – it’s essential. If you’re not sure why, you need to read our previous blog post on why mobile-first design matters. But what does it mean, and how can you apply it to your own site? Here’s a breakdown to help you get started.

What is mobile-first design, and why is it important?

In short, mobile-first design is basically designing your website specifically for mobile screens before adapting it for desktop. Why? Because more than half of all web traffic comes from mobile devices. 

Lots of people make the mistake of building for desktop first, then try to retrospectively cram the site into a state where it works on a mobile device. This rarely works well, so it’s best to plan for mobile from the get-go.

With a mobile-first approach, you’re ensuring your site provides a great experience on small screens first, then scaling up to fit larger screens like desktops and tablets. 

1. Prioritise a Simple and Clear Layout

Simplicity is your best friend when it comes to designing for mobile-first. Start by thinking about what’s most important for users to see when they first land on your site. Unlike on a desktop, where you have plenty of screen real estate, mobile screens require you to focus only on the essentials. A clean, straightforward layout is not only easier to navigate, but it also loads faster – a key factor for keeping mobile users engaged. If the site takes too long to load, users won’t hang around waiting for it; they’ll just leave.

To achieve this, avoid cluttering your pages with too many elements. Stick to the essentials, such as a concise header, a well-sized logo, and a strong call-to-action (CTA). To quote ourselves, your CTA should be “unavoidably obvious, and easy to use.” On a mobile this means it should stand out, be thumb-friendly, and appear above the fold on mobile.

2. Optimise navigation for mobile users

Mobile users often navigate websites with their thumbs, so it’s important to ensure key elements are within easy reach. For most people, the bottom half of the screen is the “thumb zone” – design your navigation with this in mind.

Here’s how:

  • Use a hamburger menu: These are the three little lines that you’ve probably noticed on mobile websites – we have it on our own site. A compact hamburger menu keeps navigation neat on mobile, and it’s what most mobile users expect. It lets you tuck away secondary options so the main screen stays clutter-free. E.g. our own:
  • Streamline menu options: KISS: Keep It Simple Stupid. Avoid loading up your menu with unnecessary links. A simpler, condensed menu is easier to navigate and faster to load.
  • Use large, tappable buttons: Small buttons and links can be frustrating on mobile. Ensure your buttons are big enough to tap comfortably and have adequate space around them to prevent accidental clicks. This space is sometimes referred to as “white space” and for more on that… We have a blog! 

3. Compress and optimise images for speed

Loading time is everything on mobile. That’s really important, so we’re going to say it again:

LOADING TIME IS EVERYTHING ON MOBILE.

Users might be on slow networks, so it’s important that your site loads as quickly as it can. People won’t wait for it to load, they’ll just leave. And slow sites aren’t good for SEO either. The Google bot knows that people don’t want to spend all of their mobile data on loading a website; they want to watch TikTok or YouTube instead. 

So, when it comes to designing for mobile first, this means using the correct format for images. WebP is best, as it significantly reduces the size of the image files, without compromising on quality.

It can also be worth limiting the amount of animation and auto-playing videos you have. These features are resource-heavy and can slow your mobile site significantly. Allow users to initiate these actions if they want to.

4. Design Content for Quick Scanning

We’re all guilty of this. We’ve all been impatient with large blocks of text, and on mobile, it’s even worse. Users typically don’t read long paragraphs – they scan. To cater to this, break down your content into bite-sized chunks and use clear, concise headings. Bullet points, short paragraphs, and strategically placed keywords make it easy for users to digest information quickly. Also, remember that screen space is limited, so avoid “fluff” content and get to the point. You can use blog posts to waffle if that’s what you want.

For example, if you’re introducing your brand (like on your homepage), use a short tagline and a brief description rather than a lengthy story. If users want more information, they’ll click through to read additional pages or your blog.

5. Test your site on real devices

Responsive design simulators are great for an initial check, but there’s no substitute for testing your site on real mobile devices. We’ve been caught out by this in the past – on a simulator, the brand-new, shiny site we’ve built looks great. On an actual phone? It needs some TLC.

So, make sure to open your site on different phones and tablets to ensure it looks good and works smoothly across various screen sizes. This step will help you catch issues that might be hard to spot in a simulation, like slow-loading images or difficult-to-tap links. And, while we’re on that note, make sure you test it on 4G (not just your WiFi) and use multiple devices. Remember caching! Once you’ve loaded the site once, it will load faster the next time since some files will be stored locally on the device. So, be sure to use incognito windows and/or a completely different device.

6. Don’t forget mobile-friendly forms

If your site includes forms, such as a contact or sign-up form, make sure they’re easy to fill out on a small screen. Long forms with multiple fields can be frustrating on mobile, so keep it simple. Only ask for essential information (you should only be asking for essential information anyway, to be honest), and use large, tappable fields with autofill options where possible.

A nice “quality of life” improvement for your mobile users is using mobile-specific keyboards i.e. switching to the numeric keyboard for phone number fields, or the email keyboard for email fields.

7. Plan for Regular Updates and Maintenance

Building a mobile-friendly site isn’t a one-time effort. As you add more content and features, your site may need adjustments to maintain optimal performance. Make sure you regularly test your site’s speed and usability on mobile, update plugins if you’re using WordPress, and optimise new images as they’re added (the EWWW Image Optimiser is great for this on WordPress – it’s free and will automatically convert any images you add). This ongoing attention will help keep your site running smoothly and keep users engaged.

Time for you to give it a go

Building a site that’s “mobile first” might sound difficult. But if you keep these points in mind then you’ll be on the right track.

If you’re ready to take the plunge, then roll up your sleeves and start building! If you need a little guidance along the way, we’re always here to lend a hand so drop us a line. Our advice is free, so we can give you some feedback on your design / ideas and it won’t cost you a penny.