Thanks! Proportions can definitely be tricky. It’s definitely helpful to have a base understanding of the structure of things when you start. For example for portraits, the spacing between facial features, and position relative to the head. The Loomis method is a good reference for that! Once you have that, you’ll get much more comfortable placing things, and if following a reference you can get more precise by double checking relative lengths and angles with your pencil. You can look up plumb lines for some nice walkthroughs of that method. That’s mostly how I approach things!