To reduce the footprint of my PCB I would like to use SMD parts, mainly resistors, diodes and capacitors keeping my basic PCB through hole.
Is there a tutorial to help me get started?
Probably not. You need to select the package in Inspector and change it to the appropriate SMD size like this:
the top resistor is the standard THT part, the second has been changed to SMD 602 by Inspector by selecting the package tab and selecting it in the pull down menu. The package needs to match the size of the component you have.
Peter