How could I improve FPS in Dark Souls: Remastered?

Hi everyone.

I recently bought DS1 Remastered without realising that maybe my PC (which is quite old) would not support it. I would like to know it there is any way to improve FPS, some solution similar to DSFix or something like that. I'm already playing it with minimum graphics, but it's not enough.

Thanks. I wish you can help me.