These are the precise settings and commands I used (minus filenames) for my reddit post https://www.reddit.com/r/StableDiffusion/comments/14jck90/finetuning_sdxl_on_an_rtx_2070_consumer_tier_gpu/
I was at the time running this version of Kohya's trainer (now very outdated): https://github.com/kohya-ss/sd-scripts/tree/747af145ed32eb85205dca144a4e49f25032d130
Some edits were made between runs, this is the lastmost settings I had.
This was ran on an RTX 2070 within 8 GiB VRAM, with latest nvidia drivers. The VRAM limit was burnt a bit during the initial VAE processing to build the cache (there have been improvements since such that this should no longer be an issue, with eg the bf16 or fp16 VAE variants, or tiled VAE).
This was ran on Windows, so a bit of VRAM was used by the OS. You'd be safer on Linux.