pitch in and (do something)

To "pitch in" means to add your help to a large group project or effort. You can use this phrase to describe helping a charity, or volunteering to work on a project at work.

help out

You use "help out" to talk about assisting with a project or a task to be done. It has a positive, cheerful sound.

Thanks for helping out!

it shouldn't (do something)

You can use "it shouldn't ___" to talk about the future. You use it when you're guessing about the future, but you have a strong reason to think that things will happen a certain way. For example:

This shouldn't take too long.

You would say this when you're about to interview someone, and you don't have a lot of questions to ask them. The interview might take a long time, but it probably won't. In this case, you can say "it shouldn't take long."

(not) take too long

Saying that something won't "take too long" means that it won't take a long time. This expression is just a bit casual.