Still on this project.....
Can you direct me towards any tutorials on this Bunnings workshop site that could offer me advice for applying undercoat?
Thanks so much
It's great to hear from you @amy2!
You might like to read through this step-by-step guide: How to paint like a professional. It touches briefly on applying undercoats. However, applying an undercoat is much the same procedure as painting.
If you'd like to post some pictures of the surfaces you are planning on undercoating, I'd be happy to provide advice tailored to your project. The most important choice is likely what type of undercoat you'll use. Recently I've been using Dulux 1L PRECISION Maximum Strength Adhesion Primer White on any surface that has more than a low-sheen to it. Traditionally you'd need to scuff up or remove any gloss paint before undercoating. This new product will adhere to the gloss surface with only a slight sanding. For a general-purpose undercoat, I go with Dulux 1Step Prep Primer, Sealer & Undercoat.
I look forward to seeing some updated images of the project and providing further assistance.