Choose your advanced starter based on its trunk line, health of the canopy & ‘potential’ for bonsai development.
Study your tree, try to find a front or preferred view.
Remove unnecessary branches that will not be part of any future bonsai design; leave stubs to create future jin (dead wood) or to be used as anchor points for wiring.
Strip bark & the cambium layer from the stubs using jin pliers, create jin with trunk splitter & jin pliers. Wire the jin, if you like, to create twists that will set in place as the wood dries out. Jin evoke the struggle between tree and weather. Storm damage! Branches are ripped & twisted off.
Remove tree from its pot. Working from the soil surface down, carefully expose the lower trunk and (hopefully) the nebari – the main roots that give a sense of age & strength to bonsai, integral to any future design.
Review the position of ‘front’ based on the entire trunkline.
Carefully untangle & if necessary, remove, any fine roots that crossover or wrap around the trunk. Do it now. Too often in the past, I did not correct tangled fine roots. They became massive woody tangles with the passage of time. Ugly.
Use a medium-stiff brush to work soil away from the surface roots.
I then like to return the tree to its original pot, taking nothing else off the root mass. Lift the tree in the pot, to be at or above the rim. Simply put more soil mix underneath, and fill around the sides of the reduced root ball. Topdress. Soak well. I add Plant Starter (Multicrop) to first watering, it reduces transplant shock & encourages fine root development. Your tree has undergone trauma. Now let it rest and recover.
I will not wire the canopy at this stage. Why? We’ve created an imbalance between the root system (still almost intact) & the canopy (significantly reduced). The tree will grow strongly, because the root mass can support more foliage. Let the canopy grow unrestrained. De-candle & reduce the number of needles, at the appropriate times in the growing season
This tree might be ready for a styling workshop in a year from now. Preliminary work is done. So the next time it’s a ‘shrub’, it will have much better structure. A visiting tutor, demonstrator or experienced bonsai Club member can then help you create a delightful future bonsai. Let it rest again after that styling. Repot in the Spring (eg 18 months from now). Be mindful that the first display container might have to be larger than the ideal pot, because you have so much root mass. Go easy with root mass reduction. Don’t rush.