What kind of spray works on sap suckers?

You can use spray made from garlic, mint and catnip. You could also plant garlic in your garden. You can also use oxalic acid, hot pepper spray or capsicum spray to save your plant from sap suckers

Simply take an empty plastic bottle, pour in a cup of ordinary cooking oil and ¼ cup of dishwashing liquid. Give it a good shake - you'll see it turn white! That’s your white oil concentrate. Label with bottle with the correct dilution rate –‘one tablespoon per litre of water’. It's important to stick with this rate because too much oil will cause leaf burn. Mix it well before and during spraying and make sure you cover the under surface of the leaves and any crevices where sapsuckers hide. The coating of oil suffocates the sap-sucking insects. In the case of the adult citrus leaf minors, it makes the surface of leaves unattractive when they are looking to lay eggs.

I think trimming should be a good solution.

Try some domestic salt, that works wonderfully well some time.

Sometimes repotting the plant helps especially trimming all the leaves and changing the soil and adding sand to the base ...I did that with one of my begonias which had a similar problem, and it was ok after that ...

I dont have any idea about planting

Garlic and mint spray might work. Even Neem oil spray is good. But first you need to trim the plant, remove the affected leaves and if needed re pot the plant for better result. Growing a few cloves around plants ( in the same pot)which are prone to such infection is a good remedy. It protects the plant and you get your fresh garlic leaves to add the flavor in your cooking.