What is the best layout technique ?

That make sense, that way you will understand the code and not just write it without knowing what it's doing. Creating a layout, which I'm sure we're talking about responsive layout, is all about the width with percentages and float. Once you are really familiar with that behavior of code you can create a simply responsive page without even using bootstrap.

For example, you want to have a page with left side that has 70% of the page and right side with the rest - 30%; You will do something like that:

HTML:

<div class="left-side">Left Side Here</div>
<div class="right-side">Right Side Here</div>

CSS:

.left-side { float:left; width:70%; }
 .right-side { float:left; width:30%; }

That way you create a responsive layout, that's it doesn't matter what device are you using, as long as you didn't set the width with pixels it will do the job You can also change the float:left to right and see how it behaves and you can also read more about the max-width to know how to center the content with like a container

That's my tip for you ; )

Thanks, i understand the percentages part but setting the position is the bit i dont .

Yes, you right, the position can be complicated sometimes, it's all depended on what you need. If you'll give me an example of code that you couldn't figure out how to manage, I will try to help