You can just keep on writing instructions in Lil, as long as there's a space between them.
(Though I'd strongly recommend hitting enter and putting new things on new lines for ease of reading and editing later. And you can add even more than that if it makes it easier for you to read what you're working on.)
So this is totally fine:
on click do thing1.toggle["solid"] thing2.toggle["solid"] end
And if you ever need to set something to a specific visibility no matter what, instead of toggling it you can also use .show -- though it's written a little differently:
thing1.show:"solid"
I hope this helps, let me know if you have any trouble!