Should you overpay loans monthly or save a chunk and pay it?

[Itsthesame]

Paying towards it decreases how long I have it but monthly repayments are the same. Should I over pay each month with the money I want to put towards it or save that until that pot is at like 1k and then do a payment then? Don't know if it's weird to just overpay £100 each month or something.

Not sure how loans really work tbh but if you're collecting more interest on it and the £100 can easily just be paid to them vs going into a separate pot to pay to them in a few months. I'd probs just set up an extra direct debit of 100 to them and have it go out each month