I make it a rule to go jogging every morning without fail.
Literal
Every-morning certainly jogging [object-を] do [nominalizer-こと] [goal-に] am-doing [explanatory-んだ].
~ことにしている (self-imposed habit) combined with 必ず ('without fail') emphasizes iron commitment. んだ (casual のだ) adds explanatory tone — the speaker is sharing their personal routine.