When discussing direction we have words to describe the basic 2D orientations: North East South West
If we expand to 3D we have a hard time explaining concepts like up or down in relation to these other units. Obviously we can say 'up', but cardinal directions allow us to combine vectors and get new transitional trajectories like North-East.
Furthermore, one travels not just in space but also in time. Because there is such a limitation on vocabulary when discussing the very real concept of space-time, we rarely think of ourselves traveling in time the same way we may travel north or east.
If we expand the set to include 3D and Time directions, we can align our thinking in space-time when we discuss vectors, traveling, etc—thus opening our lines of thought up to a more accurate and advanced representation of the world around us, and may allow us to think of things we might normally have not thought of.
Additionally, we might often consider 'north' to be directly infront of us, or towards a common fixed point (e.g. in Space, 'North' might mean sun-ward. Since on Earth it is used to mean in the direction of the northpole).
I noticed that the current Cardinal Directions have two groups (y-axis and x-axis) both with a shared suffix. __th and __st. (north south vs east west) Another 'set' in English has these Suffixes, numbers! E.g. first, fourth.
From this I borrowed the suffixes from the other 2 missing numbers (third and second). Now opposing directions in the z-axis will contain the nd suffix, and opposing directions in the t-axis will contain the rd suffix.
Ou from Outward makes Ound. In from Inward makes Ind.
Fu from Future makes Furd. Pa from Past makes Pard.
(all words are pronounced the way their roots are pronounced, so furd is pronounced 'fyerd')
Suppose I was drawing on a map with sharpie for 30 seconds. As I drew, I would go up, or down, or left, or right, in some directions I would draw much further away from the origin before returning. At the end if I were to ask you, in which direction did I draw furthest, assuming my point furthers from the origin was up, you might say 'north' (and be correct). With this new expanded vocabulary you could answer 'Furd' (and be correct).
If you visualize my drawing on the map, as a motion-trail allowing for viewing from a perspective that can see time as a dimension as well (see below), you will see that my pen, regardless of its North-East-South-West positioning on the paper, travelled, by far, more in the Furd direction (forward in time axis of spacetime).
(Note: 1 planck-time unit would be "equidistant" to one planck-length in space, this is why I can say travelling 30 seconds (furd) is 'further' than travelling 4 inches(north) on my piece of paper).
Because of the nature of like-suffixes used in opposing ends of each axis, all space-time directions can be categorized into the following format: ___th-___st-___nd-___rd. Example: North-East-Ound-Furd.
Opposing directions can-not exist (like North-South) and all opposing directions will share the same suffix (North-South).
These directions all start with a unique letter, which is important for quickly abbreviating directions. Currently you can say, N, NE, NNE, SW, etc. Now you can say any directions of the form (N,S)(E,W)(O,I)(F,P). E.g. A plane taking off, destination antarctica, will be traveling either SEOF or SWOF. (or SOF)
To get the full effect of having this increased vocabulary changing your way of thinking, you must visually experience the words. When using a word like furd, don't simply just acknolwedge that it means forward in time, we already have the word future, you must visualize the object or data set you are talking about, rotated into a higher dimension, as a vector through t-axis. Visualize a motion-trail like in the basketball image above. Then your brain will learn the concept of traveling Furd and Pard, and will more frequently think (not just in internal dialogue) in terms of space-time, not just space and time.
If you were to travel through time in a time machine, and Earth is constantly hurtling through space, consider that if you travelled one year pard, Earth would be very far away from the spacial location you are in "now", you would be floating in space and in one year's time Earth would slam into you (this probably is violating inertia but it's just for example). So, when time traveling, it's not enough to travel furd/pard you must necessarily travel in other spacetime cardinal directions as well, otherwise you are de-facto teleporting relative to the world around you.