Play when you won't be bothered and immerse yourself as best as you can. You'll be hooked up by this game pretty fast and nothing is more annoying than someone talking to you or ambient noise.
Try as much as possible to play through en entire episode in one play session. Devs have repeatedly said that episodes were designed to be played in one-shot. The narrative really support this play style and is devised to always keep you on edge at the end while allowing for quiet moment midway through episodes.
Explore, read everything, talk to everyone. I may depends if you enjoy this or not but this game is a textbook example of environmental storytelling. If you rush through the game, you'll just get the main plot but there is so much more. The world is filled with secondary and tertiary story and a good part of character development is told this way. Don't be afraid to be nosy, whatever the game might imply, you can always take your time to search every corner of each level. Also the amount of detail in this game is amazing and there's always a nice thing to notice, this range from Easter eggs to major foreshadowing of future events so be on the lookout.
Do not underestimate sound. This goes with immersion, but really, from the licensed tracks to the general ambient sounds, the audio in this game is just wonderful. Be sure to fully enjoy it.
Play at least until EP2. Some people are put off by the cheesy dialog of EP1 or the teenage drama feel in the beginning. I personally don't mind it but we all like different things. Anyway, play at least until EP2 even if you're not sure to like the game. Past this point if you're still not hooked up, you can give up on the game. But too many people stop after EP1 and miss the really interesting stuff.
Play at your own pace. Some people prefer to rush the game, some prefer to let things settle down between each episode. It's really up to you and there isn't a "good way" to play the game in this regard.
Treat this subreddit (and to some extend, the internet) as a no-go place. This sub can be spoilery at time, and we do sometime forgot about spoiler tags. Same with anything on the internet related to this game. Avoid all of this, you do not want to spoil yourself with this game. Also, official trailers are sometimes filled with spoilers. It might seem ok before you start playing because you do not really understand what is happening in the trailers, but once you started the game, I would recommend to avoid everything that is slightly LiS related, this thread included.
depending on how you react to the game, these might be useful recommendations too
Have some tissue by your side. I mean, really, the more you hold on your tears, the worse it'll get.
Come back here and share. First, you'll fucking need it, so I'll spare you a couple of hour of intense distress: what you really need after EP5 is to talk and share about this game. Don't waste time figuring this out, once EP5's credits roll head back there and tell us anything you want to share even if it seems stupid, this community is really welcoming and you'll probably only get positive feedback. Also, it will greatly help you with the overbearing emptiness you'll be experiencing, and some of us thrive on seeing new players share their thoughts.
You'll be changed. For most of us, this game is a part of our life now. You can only play this game for the first time once, and when it's done, you'll be on the other side, with all of us. It may not be a life changer of course, but it's a once in a lifetime experience for sure.
It doesn't end with EP5. I'll speak for myself here, but this is true for most of us in this sub. I played through the game in one week but 3 weeks after I'm still shaken by my playthrough. This is the only game that as impacted me longer than its play time, so be prepared. You might finish LiS in one week, but your LiS experience will extend way longer than this. Time-wise, it's actually the most prominent part.