Others have mentioned most of the important points, but I would like to add few more points which I have learnt in my career.
We should always remain updated to find out what is going on. Like the way artificial intelligence and internet of things are being used in industry, we should be aware of these, otherwise we shall be lagging behind.
Gathering knowledge is most important but how to use this knowledge is similarly important. Say we are designing a metal cylinder. To make it suitable for the application its design has to be somewhat which is not suitable for bulk production. Hence, only knowledge about design is not important to a designer, knowledge about production is required and to be utilised properly.
Lastly I would like to add that there is an old saying that hard work always pays off and it is something we have control on to progress in our career. But we should always be careful on the direction where we are putting our hard work.
Hope this will help you.