The space walk cannot be entered without the spacesuit being worn. You cannot access your Pip-Boy or use any weapons on the map. There are no enemies, although you can see some aliens scurrying around the corridors below you. You must locate three panels that stand out slightly from the ship's hull. They are emitting a yellow glow to make them obvious. Activate all three panels and the transporter to the next portion of the ship will become available. The transporter is located directly in the center of the circular hull you are traversing.
The space walk is a one-way trip. You cannot return to the airlock you emerged from; you must use the transporter to proceed to the next level.
If you attempt to walk off the edge, you see an animation of yourself floating off into space while trying to grab onto the ship's hull.
Make sure you're not relying on any edibles or drugs (e.g. Buffout) to give you enough Strength to move (i.e. you're carrying too much weight). Once you're outside, you can't access the Pip-Boy, so if the effect wears off and you're over encumbered, you can't do anything about it until you're inside again.
If you have a drone following you it will not follow you on the spacewalk but once you have reached the final teleporter he will teleport with you.
A second before you start walking it will show your oxygen level and say 1 rad p/s.
If you look through the see though parts of the floor you can see two aliens running in a continuous loop around the ship. You can also hear their shoes squeak, even though there shouldn't be any sound in space, this may be explained by the sound vibrating through the hull and your suit. They will stop at certain points and look around as if they have a feeling you are nearby.
The Pip-Boy and Pip-Boy glove are visible in third-person. This is probably an oversight by Bethesda. However, if the Pip-Boy glove is removed via console, the spacesuit glove appears larger on the left hand than the right. This possibly shows that the player's hand being exposed to space is more of a glitch rather than a shortcoming.
Turn your Pip-Boy light on before going outside. While outside you can turn the light off, but you can't turn it on.