Like the others I just get a bit of a production line going....line all the bottles up in my laundry sink, put a funnel in one, and pour in no rinse sanitiser to 3/4 full. Take the funnel out and move it to the next bottle. Pick up the first bottle, hand over the top and shake a couple of times. Then pour the sanitiser via the funnel into the next bottle and repeat.
Line all the sanitised bottles up on the bench as I go. Then when they're all done, I set up the FV with the little bottler, and as I pick up a bottle to fill it, just tip the remaining couple of ml of no rinse into the sink, then add a carb drop (if i'm using them) and fill. I hold it with one hand as it fills, then pick up the next bottle with my other hand and drain into the sink.
The only time I use a bottle tree now is when there's been a big session and I have multiple bottles to clean...I clean them then put 'em on the tree to dry for a day before boxing them for the next bottling day. If I only have one or two bottles to clean then I invert them into a 1 litre round bottomed measuring jug that sits next to my laundry sink rather than use the tree.