The big question: how do you system hop? If you were to ask another system this, they'll most likely tell you that "it depends". While this is true, it's not a satisfying answer for the curious crowd.
There's a wide range of methods out there, to the point a single step-by-step guide couldn't be written. Instead, let's dive into the common methods and how they work for other systems.
Common ways to travel include, but are not limited to:
Astral Projection: Some headspaces are located (partially or solely) in astral. If that’s the case, members can get away with astral projecting as a method of travel. Otherwise, a few systems report that they mimick astral projection methods to system hop.
Bridging: Most systems that regularly travel have a bridge, gateway, door, portal, or entrance to the headspace they travel to and from the most.
Narrating: As a way to visualize the process and retain memories of their experience, some systems narrate or act out their experience.
Visualization: The member visualizes themself in the destination, entering the headspace (usually by visualizing walking through a door, portal, or gate), or imagining a teether connected to their body.
If you believe astral projecting or mimicking projection methods would work for you, check out /r/AstralProjection's Wiki! It has a variety of information, methods, tips, and tricks.
Creating an entrance wildly depends on how your headspace works. If you can conjure up objects simply by thinking about them, bridging may come easier to you than others. Here are a few ways to create a bridge:
Both parties conjure up entrances in their headspace that look almost identical;
System members from both systems physically build an entrance;
Redecorating, repurposing, or reusing an existing entrance
Sometimes decorating the entrance to look like the other system's headspace can be helpful! It can strengthen the connection and easily communicate its use to other members.
A few tips for narrating:
Sometimes narrating with PluralKit can be helpful as it clearly shows who is narrating and/or traveling;
Make sure you "set the scene" by detailing the location;
Focus on action and dialogue, as these are the part of traveling that is often forgotten about.
Gamemaster, storytelling, and movie narration guides may be useful to you! Here's a WikiHow article on narrating.
Visualization heavily varies, but using diagrams, maps, drawings, moodboards, Pinterest boards, and playlists can help travelers visualize their designation. In some instances, using similar visualization techniques that witches and energy workers use (such as the apple exercise) can prove useful.