One good footwork advice I and all other senseni can give you in all the footwork (ashi-sabaki) is to return to the basic stance. You do not want to have a crocked stance after moving.
You can move however you want but must go back to the basic stance.
Concentrate on your ashi-sabaki and be aware of how your feet are moving at the very beginning of ashi-sabaki acquisition.
There is nothing difficult about thoes ashi-sabaki except hiraki-ashi.
It is very common to cross the legs in hiraki-ashi. Of course, it is OK to perform such ashi-sabaki once you have acquired the basic ashi-sabaki.
But at the beginner's level, it is not wise to cross your legs or not to return to the basic stance.
Why can't we cross our legs or do we have to go back to the basic stance while we will NOT have to when having become an advanced student?
It is because crossing legs and other ashi-sabaki such as tsugi-ashi and ayumi-ashi are very easy to do. In other words, you don't have to learn these ashi-sabaki.
But okuri-ashi is very hard to do. The hardest ashi-sabaki in kendo is the basic ashi-sabaki. Be patient and thoroughly acquire the ashi-sabaki.
Many people concentrate on the striking part of kendo. But it is much easier than okuri-ashi.
Thus, if you are a beginner, even though you are attracted to striking part of kendo, I suggest that you should work on ashi-sabaki. Especially, if you do not want to stop improving in the future.
Please refer to an article called "Basic Kendo Footwork" too. In the video, there are some tips to improve your kendo ashi-sabaki (suri-ashi).
Hope the video helps.