A good system is to keep a wall calendar with all of your assessment dates on it. A countdown system can be helpful, eg "2 weeks till hand-in of X". You will probably find that you have multiple assessments due around the same time, maybe even on the same day, so it's essential to have a system where you can keep tabs on each and every assessment.
In general, I would suggest a leisurely 4 weeks for an assessment, which covers reading, note-taking, drafting & revising. However, this won't always possible due to time contsraints, so a more stressy 2 weeks is also eminently doable. Anything less than that is likely to result in patchy work unless you are one of those people who can write brilliant essays off the cuff.
Avoid handing work in late because, without extentuating circumstances, you will get a flat 40%.
Always check the module assessment details for assessment weightings, which can help you to prioritise assessments - for example if something is worth 75% of the module, it's clearly more impactful than something worth 25% - but you also need to check whether you need to pass all assessments to pass the module.