1. One word responses aren't the best, 'Cool' or 'Nice!' may save time, but put the poster in the awkward position of wanting to ask for specifics. If you have time say more! Or perhaps delay until you're free-er!
General praise can be nice but often friends put specific details in for specific reasons. Mentioning specific things you like can lead to discussion, and serves as a reward for said friend's attention to the small things! See if you can relate!
This...in general even outside of commentary is good! If someone shows you something they made and wants to talk about it, asking a few simple questions like 'Why did you put X in. It's neat!' can surprise you with the stories they bring.
If you do have a critique, don't make it your first reply! Criticism is fine if constructive, but often your friend is excited to share, keep that excitement! That way your criticism won't staunch that exuberance when it hits.
A lot of times when someone shares something, the first reply they get is 'This reminds me of something *I* made/like'. It's fine to flow into that, but try to keep the focus on this new thing they want to share for a bit first!
This is mostly a tip for people you really value/appreciate? It's impossible to do this always, but if someone is important to you, what they make is important to them. Spend just 10 minutes instead of 1 and you'll be shocked at how much it means to them.
Really, if you do this one, the others will come naturally? Think about the last time you shared something, and the response you would have liked, or how you would have liked criticism delivered. You'll find yourself doing these things almost on automatic!
If you have friends in creative lines of work/hobby, you would be surprised how rare a genuine, long conversation about what they make actually happens! If you can provide that catharsis, it's good for their mental health and possibly yours!
Onwards!
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