Aether travel between planets is done by sailing on currents in the aether. To begin your journey you must take a zephyr airship into the clouds and penetrate the atmosphere, you can then proceed to the docks to board a ship.
Aether travel has two main versions. Sail and solar
Sail ships travel is restricted to the paths of the currents in the aether, which can often change and be interrupted by natural causes, however travelling in a current is far quicker.
The advantage of a solar sail is the ability to travel in any direction so long as the sun can reach the sails, though this way of travelling is a lot slower
Most sail ships have a combination of both, small solar sails powerful enough for redirecting and docking