You need a silicone caulking tool, and a video. I have spent many years caulking like a fool listening to other fools who spray water and use their thumbs. Don't. Use the tool. Use the kind with a little oval tip usually (I mean, there are exceptions with harder caulks but for softer e.g bathroom caulks this is more superior.)

There's one UK guy on YouTube that convinced me of the evils of water/iso sprays and the beauty of the proper silicone caulking tool.

The little wedge shaped caulking tools btw are not enough, as you need some stick to it so you can get around certain angles/items.