Mobile websites design begins with an important fact. Most of your visitors are holding a phone, probably in a queue, possibly while a toddler pulls on their arm. They won't strain their eyes. They won't zoom in and out read this. They'll simply go somewhere else.
My aunt learned this the hard way. She tried to order a pizza from a local shop's site, missed a tiny button, and ended up with three pizzas. "Well," she said, "at least the neighbors were happy." The shop was thrilled too, but that's good fortune, not a strategy.
Give Thumbs Some Space
Screens got bigger. Hands didn't. Put the main actions where a thumb naturally rests, within easy thumb reach. Buttons need plenty of room, roughly the size of a fingertip pad, with gaps around them.
If two links sit so close that a tap might hit either one, you've built a guessing game.
Performance Comes Before Looks
A gorgeous page that takes six seconds to load is a gorgeous page people will abandon. Compress your images. Remove the giant background video. Cut the scripts you added "just in case" three redesigns ago.
Test on a reasonably priced phone on an average connection, because that's real life. The office Wi-Fi is a different universe.
Make Your Text Easy to Read
Set body text at around 16 pixels or larger. Keep lines short. Break paragraphs early and often. A wall of text on a small screen feels like an actual wall, and nobody climbs those for fun.
Contrast matters as well. Pale gray text on a white background looks elegant on a designer's monitor and can disappear on a phone under bright sunlight.
Trim the Forms
Every extra field can lose you visitors. Ask for an email, maybe a first name, and stop there. Skip the fax number—yes, somebody out there still asks.
Use the appropriate input type for every field, so a phone number box opens the number pad instead of making people hunt for digits. Small kindness, big lift in completed forms.
Don't Let Pop-Ups Take Over
A full-screen pop-up on a phone is a digital ambush. Search engines dislike them, and so do humans.
If you really need one, use a small banner with an obvious close button, and give visitors a few seconds to read before you interrupt them.
Test on Actual Phones
Emulators lie a little. Grab three actual phones, old and new, and try to finish your main task on each.
Hand one to a friend who isn't techy and keep your mouth shut. Watch where their finger hesitates. That hesitation is your next set of improvements, written in fingerprints.