It might go without saying, but …
… learn to do production art
You really need to understand the ups and downs of trying to bend a DCC tool or a game engine to your will. You have to appreciate the suffering of the non-technical artist who is overwhelmed by the complexity of UI or the opacity of documentation, or the number of stupid hurdles needed to jump through to accomplish basic tasks.
You won’t likely be top-tier as a content creator but you should aim to be at least moderately competent in at least 2 of the main areas (modeling, texturing, shading, lighting, rigging, animation) . Ideally, you should be capable of at least pushing the right buttons in all of them – but for a couple you should really be able to tell good from bad, not just working from non-working. Get some feedback from artists and art-director types, learn how to talk about color and composition and form or silhouettes and timing and camera framing.
A big part of your future will be acting as a translator between different disciplines that talk past each other – it’s important to be able to speak both the technical and the artistic dialects. Likewise, a big part of your job will be knowing when to quit – when the problem is technical, when it’s creative, and when it’s just a screwy workflow or bad direction. You need to be enough of a practicing content creator to have some opinions on that before you get too buried in technical detail.