When starting out I would try to get some of the bigger areas, so you have a bit of a body to anchor the rest of the work in. Like the red diagonal markers which are at the top third of your picture.
Once you have a big island you can start working on the smaller islands and only then fill in the single stitches in the area.
When you would that method you will see that you do not need as much parking, you will have more enbroidered space to use to move your working thread around to where you need it.
As in the other answer, move to where you need it if it costs less length than stopping and starting again.
A few parked threads can find a spot in a small portable loop.
If you need more than those, bring the thread outside the ring and pull it through the fabric and take the needle off. It might be needed to do that within and outside the loop to make it stick where you want it.