How to optimize your game?

You should already start optimze it from the beginning.
Create your levels with the highest setting, if possible, try to get a smooth framerate.
Remember, much trees could kill your framerate, also many NPC.
If you've a good pc, try to optimize it for 60fps or more.

Why?

Later, when the user/player play your game on a medium pc, he will still get a good framerate on medium settings.
So, if your game runs on 40fps with high settings, it should run with 50-60fps on medium settings.

I remember the Amiga & C64 games had sometimes bad framerates, but we loved the games anyway...
Today the gamers get annoyed when they've only 30fps with their gaming pc... so keep that in mind.
PC gamers are more hardware adiccted than console gamers. So you need to give them a smooth experience.

If possible not start your level designing with medium settings, sooner or later this will cause trouble.

Great advice!

Yeah good advise indeed!

I have been designing assets for one of my game ideas, and was focusing on getting the models looking good on Medium settings, but I still test it on high settings with a goal of 60 FPS for highest setting (we will see about that as the game develops), that way it should purr much better on medium spec PC - well I hope anyway.

My PC is not that highly specked, so that will help as well, but there are PC's out there still with much lower specs than mine I guess.

Thanks for tips MooKai

Reliquia....

As trees were mentioned here's a quick tip:

Collision can be a frame killer, especially on high poly entities, trees tend to be fairly high poly compared to mist entities.

If you have a lit of trees then turn off collision I all but the ones you really need collision on, and try to use box collusion where you can if you need collision.

Also, for those who know how to model, make some decals and use a screen shot of a tree as its texture, and use them for distance trees the player won't ever be close to.

IF your using vegetation... avoid using it at Highest setting. Also reduce the terrain draw distance.

I wasn't bothered about animated trees so I replaced the fpe with a more default one ...
Ones i changed are now static and it made a huge difference in speed ....

I think you can also kill the performance from UE4 or Unitiy, if you're using to many trees with a high poly count.
turn off the collision from trees... only if the player can not reach them. else they will complain that the trees have bug, because no coll. detection.
also fog is a good tool for performace, if you're using fog, you can set the occl. slider to 100% and noboy will see that the models just pop in the scene...