Basic Technial Illustration Photoshop
Isolate the cap at the end fill with blue and set blending mode of layer to overlay
Now for the pen part. Just like before. New layer get a nice smooth brush white color set blending mode to overlay and crate highlights for the pen
Ad some effects and BAM!
Bevel and Emboss
New Layer fill with white and set blending mode to overlay. this will enhance the highlights more
Select specific area new layer fill with white and set to overlay
Select specific area, new layer, Hold ALT Layers tab merge visible. you get his