The above represents a 4-word advice, consisting of 12 distinct letters.

Each digit that is not a square of a positive integer represents a certain letter, one-to-one correspondence.
Each of the other digits represents a concatenation of 2 or 3 letters, at least one of these letters is represented by a non-square digit as well.
The spacing of the phrase was left intact.

What is the advice?

4 is you.

Now only one of the remaining digits  represents a  concatenation of 2 or 3 letters.

S  O  L  V  E     I  T  !