Yeah, what John P shared is very good.. In winter, make sure that if the temps are going to get low, like minus or 1, 2, 3, then the substrate the Olive is in, is not wet.. try to control how wet it is.
As the blog link says, a wet substrate in 1,2,3 feels like -2,-3,-4 to the Olive, which it will not appreciate.
They start growing, slightly varying with the weather that year, around Early to mid June for us.. and stop end of August. Its been recommended to me before to buy a heat pad to the put the tree on, giving it heat for longer and extending the grow season, but Its not something I've tried. Yeah full sun of course.. needs heat, not just sun.
I had mine in 100% molar clay/cat litter, for 3 years. It did really well. I've changed to mostly Pumice now, with some molar. According to Online, it should be a better mix for it, Pumice is better for Mediterranean species, allowing them to dry out for longer, but will see how it goes! Your Olive looks to be in a very organic substrate, which is total opposite of mine, so I am interested to see how it goes.
Prune the leaves pointing down, a new branch will grow there when you prune it back, which you mostly don't want.
I got great growth and thickness from mine, but only after allowing it to grow wild for 2-3 years. You might not need to that that, depending on what the branches are like.
There is a pest that I see on them regularly, doesn't do much harm, forgotten its name... They curl over the leaves in to each other, with a web and have a small larvae or caterpillar inside.. I think its called a wasp of some sort, dunno. Not a big deal, might see a few, I just unravel the leaf with my fingers, remove the web and whatever insect inside. That's the end of that..