important is:
build a trigger brush (block tool on the left-current texture browse on the right-filter "trigger" and chose the yello/orange one now create an info_target entity (entity tool on the left-objects on the right and choose info_target)and click in the 3d view where you want it to be now press alt+enter name it what ever you want
i named it "teleport" click on your trigger brush and press ctrl+t and under class choose "trigger_teleport" click "remote destination" and choose your info_target (in my case its "teleport") so that was it now in your map when you touch the trigger brush you will get teleportet to your info_target (both is not seen in your map so its usefull to mark your trigger_teleport)