caterpillars on tomato's

I have just found small green caterpillars on my tomatoes  how do I get rid of them before I have no leaves left please 

Tom moth , caterpillars can be green or brown and i think it`s a pick `em or shake the plants and then pick `em up job.
Luckily they only seem to appear in small numbers.

I squish every single one I find and I squidge the eggs. The ones we have here are little green monsters that burrow into the tomatoes, turning the insides into unappetising pulp.

They destroyed 20 of my plants last year, the whole lot.
You need to keep doors and windows closed on th greenhouse at night, it's a moth laying eggs. The caterpillars start off green and are tiny, as they get bigger they turn brown. When little they eat the leaves, when disturbed they drop off and hang on a thread. When they are big they bury into the tomatoes. They are very good at hiding.
I haven't seen one on mine this year yet but am vigilant! I will be spraying with a salt solution. Tried washing up liquid last year and that was useless.
Last year a lot of mine were big by the time I realised what was going on, I found cutting them in half with the secateurs was quite effective.

last year i had a few Hebrew Character moth caterpillars on my indoor toms...

I have these caterpillars too, and referring back to last year and a well known search engine tells me they were also Hebrew Character moth caterpillars, either green or brown.

They eat lots of leaves and the odd tomato, but I pick 'em off and squish 'em, and they don't seem to appear in large numbers anyway.

Phill