Don't forget to remain always within view (4,2,5)

'always within view' is the definition.
'keep in sight' can be an answer for 'view' (thesaurus). I am not certain of the 'always within' bit.

'don't forget to remain' is the wordplay.
'don't forget' becomes 'insight' (I can't explain this - if you can you should believe this answer much more).
'to' says to put letters next to each other (I've seen this in other clues).
'remain' becomes 'keep' (keeping is a kind of remaining).
'insight' put after 'keep' is 'KEEP IN SIGHT'.

Can you help me to learn more?