Updating 2 plugins

Hi,

I’d need to update pretty link lite and sexy bookmarks to their latest versions. Do I need to unactivate them first to be able to do this or can I just do it directly..? Is it as easy as it sounds or will these updates potentially cause some website-function issues if they don’t go correctly? I’m asking this because I’ve not updated any plugins before and had major issues with some wordpress updates some time ago.. ?? So I don’t want any issues with these small updates..