First, take any two fingers and play the intervals of any chord in any key up and down over 3 octaves. Do this with one hand then try together. Of course emphasise keys and chords you don't know so well to reinforce them. CM7 would be: C/E, E/G, G/B, B/C, etc... the variety of chord types and keys will give your fingers a nice workout!
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Secondly, do the same but with octaves! E.g. take Fm7. LH starts on F as an octave, right hand on the A, then ascend and descend 3 octaves or so in this way.

Aim for endurance. Don't do these 'ten times'... do them until your forearms or fingers start to ache. Personalisation is always key so never do exactly what I demonstrate; do what works for you in terms of octave number, chord type and tempo. Highlight one hand more than the other, etc...

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