How do I make beach waves / loose curls really really last?

[Chicinwellies]

Be it tong or product would love your advice . I have long fine blonde hair but lots of it.
Aiming for this kind of wave

I have naturally poker straight long thick hair so I’m not sure how useful my advice would be but...i tend to find my hair stays curled if I use sea salt spray before curling, otherwise my hair is too soft to keep a wave/curl. I would have thought it would work well with your hair too?

Sea salt spray

What is your natural hair texture / quality like? If you have thick even hair without any flyaways or damage the waves should be able to stay all day with seasalt spray and some kind of holding spray. Otherwise you will just end up with a frizzy mop

Thank you. Keen to avoid frizzy mop and not something I suffer from. Just 5 minute waves.

Can I also ask how to stop it looking frizzy, my hair curls nicely but after a couple of hours it not only loses the curl but becomes really dry looking and frizzy. I spray it with heat protector to begin and finish with hairspray and a touch of serum.

I use mousse then blow dry, hairspray then brush out, curl it then sea salt spray on my hands to mess it up a bit