Another code I like to use to make things invisible is \phantom{}
It will makes whatever you put inside invisible! I sometimes use it for spacing
Also there is the \hspace command which can be used to make a horizontal space of a specified length.
For example, the code: a\hspace{3cm}b
makes this:
\(a\hspace{3cm}b\)
So there are 3 cm of space between the a and the b.
(Also here is a list of the different types of units of length it recognizes)