I open path effects (seems a long way just to change line size) and nothing happens. I read online to change Preference settings, but there is no line size selector, drop down, pop up....etc.

Arg this is so frustrating - can someone help me? I have inkscape .91

It depends on how you want the line width increased, as to which way you do it. If you want the whole stroke ("line") to have the same width, use Object menu > Fill and Stroke > Stroke Style tab > Width. (or there's a shortcut in the Style Indicator area of the Inkscape window http://tavmjong.free.fr/INKSCAPE/MANUAL ... atomy.html)

If you want the line to have a variable width, maybe the Power Stroke LPE is what you need (although there are also other ways). Unfortunately the manual hasn't been updated to 0.91 yet . Here's a quick explanation.

-- Draw the path
-- Path menu > Path Effects > Power Stroke

If you're not already using the Node tool, switch to it. Now you will see 2 kinds of nodes. Gray and pink. The gray nodes adjust the original basic path. The pink nodes adjust the width. Grab a pink node with the Node tool and drag a little. You'll see the path get wider. However, you'll also notice that the path has changed. Now it's not a solid path anymore. So you can either fill that with the color that you want for that "line", or use another technique.

Other techniques:

-- Pattern Along Path, and there are a few ways to do it. Fortunately, plenty of manual documentation Extension: http://tavmjong.free.fr/INKSCAPE/MANUAL ... nAlongPath. LPE: http://tavmjong.free.fr/INKSCAPE/MANUAL ... gPath.html

-- Use either Pen/Bezier or Pencil/Freehand tools in Spiro Spline mode http://tavmjong.free.fr/INKSCAPE/MANUAL ... ths-Pencil or http://tavmjong.free.fr/INKSCAPE/MANUAL ... ths-Bezier Or there's a Spiro Spline LPE: http://tavmjong.free.fr/INKSCAPE/MANUAL ... pline.html

If you're not sure which one you need, please feel free to explain in a little more detail what you're trying to accomplish. We'll be glad to try to help