Don’t panic, there is plenty you can do to get ready. Worst thing would be to stick your head in the sand until the day looms. You need to arm yourself with the right skills and techniques to make sure you are ready to do your very best, whatever they throw at you.
What you want is to be able to show what you are capable of on the day. There are ways to prepare for this, even if you don’t know exactly what exercises or tasks you will be facing.
Most candidates don’t bother with this and that’s where they come unstuck.
Understand the role of the competencies– you get that the assessments are going to be interested in how you do things and not just what you know, right?
Practice reading and writing– speed is important and if you are rusty at these 2 skills it will really hold you back.
Do some self-review– some of us are better at reflecting, accurately, on our strengths and weaknesses than others. If you aren’t sure, get feedback. You need to know what you need to work on and what you need to play up as a strength
Practice with some practice exercises– most people don’t attend assessment centres very regularly so the exercises can come as a bit of a surprise. Use one of the many resources available to get familiar with the type of exercises you can expect and get some practice of dealing with information in this way.