Hi.
If I'm not mistaken you are after that gradient fill and for that outline with pointy highlights.
The gradient fill can be added by the fill and stroke panel alongside the stroke.
If you want a custom shading on the edges, somekind of filtering would be a fitting way.
Either that being blurring objects manually and clipping them, or using a more complex one, the result not transfers well to pdf-s so we'd need to know more about the details.
Wether you are after a full vector drawing or not.