how far east do you go, before you start heading west ?

I live in Europe and my country is all in the same time zone that is GMT. If I go east I will come to +1, +2, +3 until I get to the International Date Line. If I go west by by 5 hours I will reach the USA. I continue to go west until I reach the International Date Line. It is in the Pacific Ocean. The North Pole is at the top and the South Pole is at the bottom. The Equator is in the middle and the tropical marks are the Tropic of Cancer and the Tropic of Capricorn. Round the world routing might begin London to Singapore eastbound or London to Los Angeles westbound. It will all change once thee traveler goes over the International Date Line.

Well east-west is different from north-south. You can travel east forever, going around and around the globe. The same holds true for westward travel. East-west is based on the turning of the earth; move in the direction that the earth is turning and you are headed east as long as you keep going in that direction. North and south travel on the other hand is based on its relationship to the north and south poles. Travel north towards the pole becomes travel wouth once you hit the north pole and move beyond it. This is probably easier to explain with an actual globe.