There reaches a point in every project where it is time to share it with others. In game design you need to get it in front of play testers to see if things work the way you intended them to, and when writing you need your beta readers to tackle the text and share their initial impressions. When this time comes you need to do three things:
Put your ego aside
The project is no longer about you. Not that it ever was. But now, more than ever, you need to remember and understand that your game, story, novel or other creative endeavour is about the end user. Whatever happens next isn’t about criticizing you, or pulling apart your precious baby. It is about making it the best it possibly can be for your intended audience. So don’t let your ego get in the way, don’t be so arrogant as to think you have everything right. If that was the case you wouldn’t need play testers or beta readers. Fresh eyes and fresh perspectives can provide new ideas and opportunities, spark previously unthinkable thoughts.
Listen to your feedback
If you have asked play testers or beta readers or whoever to try your thing and give you feedback, then listen to them! You don’t have to act upon everything they say, think or feel, but for goodness sake, give it all a fair hearing. You have hopefully chosen people you trust to provide some insight into your work-in-progress, so now heed what they have to say. Your feedback-givers have invested some time in your work, are passionate in some way about what you are doing. Reciprocate their effort by putting as much into the hearing, reading, analyzing and investigating of their comments.
Stick to your guns
By all means listen to the feedback you receive, but also stay true to your own vision. Nobody knows your work as well as you do. Some feedback will be better than others, so it is part of your job to sort through it, grab the gems, and acknowledge the rest. Sometimes the most well intentioned feedback is just wrong and in these instances it’s totally okay to ignore it. The real trick is knowing which bits of feedback are which!