Can I make my website scale to ipad/tablet size or mobile phone


I was wondering if I had the option to make my website scale to size on mobile phone or tablet/ipad? Because when I use responsive mode and I start adjusting it to the right size and than I save everything on my normal website format changes..

This is really annoying so I had to start all over again to make it right. Now I don't try anymore because I don't want this to happen again. I also don't want my site to change everything in these modes.. I want it just to scale to fit the page..