So your book has (or used to have) a DJ but doesn’t have a catalogue in the back.
Your book therefore dates to between 1958 and 1965.
Next look for the Ladybird logo somewhere in the book or on the DJ (if there is one present). Does the logo show a ladybird in flight (open-wing logo) or closed wing logo?

On the right the later, closed-wing logo.
If open wing, then your book dates to between 1958 and 1961. If the closed wing logo then your book dates to between 1961 and 1965.
The end.
(To find out if your book is a first edition, you need these pages)