The Golden Rule is: when at sea, go aloft on the windward side; when at the dock, go aloft on the water side. When at sea, the windward side of the shrouds will be tighter and less steep if the ship is heeled over. Also a gust of wind will tend to push you into the shrouds instead of off them. If you must go aloft on the wrong side, you can go up the inside of the shrouds. When at the dock - well, falling into the water is far preferable to falling on a dock.
The author - just under the fighting top (the platform visible in the pictures below). Black lines (tarred) are standing (stationary) rigging. The white lines are running rigging that moves - don't depend on it for a hand or foot hold or you may end up in flight. My next step here is to grab on to the standing rigging shown and climb around it to get up on the fighting top. Once there I'll need to step out onto the topmast shrouds to climb up to the tops'l yard (in the picture below, the next yard above the yard we're working on). Depending on how it is braced, stepping out on a yard can entail a big step over lots of high, empty space onto a single little foot rope. Of course this all becomes much more interesting when performed while underway - even in relatively calm seas.
Furling a course. From left to right: Guy ('Gee-guy'), Fitz, me, Jamie, and Andros. For a harbor furl, the sail is stuffed and rolled, then all hands jerk ('bust') the furled sail up on top of the yard before making fast the gaskets. A sea furl is less carefully layed up. Harbor furls are a must when coming into port - especially if there are other tall ships around. The tops'l and the t'g'ants'l in this photo are 'in their gear' - that is, they have been hauled up to their yards (struck) by hauling lines from the deck and are ready to be furled.
Way more people than you need to furl a tops'l. The long white lines hanging straight down from the yard are sail gaskets - lines used to tie the sail to the yard when furling. When the sail is loosed, the gaskets are made up into gasket coils and hung over the yard on the sails' front. The short white lines are reef points. In this picture the course and tops'l yards are braced for a port tack - the t'gallant yard is almost braced square.
If you've ever wondered how one stays up there, the answer is the foot rope they're standing on. The loops hanging from the yard arms (ends of the yards) are 'Flemish Horses' - a foot rope for working the yard arm. The crew prefers to go aloft in bare feet. They say they get a better feel for the rig.
A view of the deck from the fore fighting top .
The bowsprit and jibboom as seen from the fore mast's fighting top. In the lower right corner you can see the fore course yard (braced for a starboard tack).