whether you are new to html/css or an old master , and you are using your notepad and a browser to design your webpages , it maybe bother you to use that ctrl+tab (to change your active window) and pressing that F5 key (to refresh) to see the changes of your design in that browser ! use this little piece of code on your html head and save it and reload your browser JUST for one time ! and after that , after any changes you make in your source code , just push that ctrl+S (to save the changes)and wait for 5 sec or less (you can customize it below ) to see the changes in browser , so ;
1 ) put this code on your source code , under the head of your html ,
<META HTTP-EQUIV="refresh" CONTENT="15">
2)customize the time you should wait to see the changes under content attribute
3) save your source code
4) refresh your browser for last time
5 ) from now on , any change in the source will automatically appear in your browser , after you save it !!