I helped a woman escape like this ( it was harder as she had two small children to get out as as well).
She snuck a lot of stuff out of the house in the weeks before she left. She set it up first by doing “ spring cleaning “ and clearing out genuine junk and taking it to the charity shop. Her husband always complained that the house was messy / kids had too many toys etc so he was happy that she was tidying up.
She made a big thing of cleaning too and rearranging things , saying that she realised he was right and that the house DID look so much better. Of course she knew that this flattery would work and not make him suspicious.
She got a lot of things out and into friends garages / sheds etc . Out of season clothes, kids toys, a small number of kitchen and household items that he wouldn’t miss, random things like some tools from the shed etc. anything that would costs money to replace ( she was a SAHM and was going to be dependent on benefits so every penny counted ).
She wrote a detailed list of all the things that had to be packed on the final day , room by room.
on the last day, as soon as he went to work, about 6 of us all arrived at her house with boxes , suitcases etc . We each packed up a room, filled our own cars and mostly took things home with us, to our garages etc as she was going into a refuge and didn’t have space until she got her own housing association flat months later .
We dismantled and packed up the kids beds and cots, small furniture like chests of drawers , table lamps etc . We got all the kids clothes and toys and all her clothes, lots of kitchen items .
It sounds like you are in a different position @Professionallytorn and are going to stay with family. Even then I’d think carefully About taking everything you care about from the house. It’s not uncommon from men to smash up things once you are gone, so don’t assume you can come back later and get them.
Take photos and a video of each room before you leave, in case he says YOU trashed the place.
You need to take meter readings and contact people like utility providers on that day so he domestic run up bills in your name. Tell them you are fleeing domestic abuse.
As you are going to family he will soon find you so you must MUST get legal advice before you go, to find out how to protect your relatives. You need to know what to do if he turns up at their door .
You need to think of the worse possible things he could do and plan for that
eg emptying every joint account , emptying your own accounts that he has a password to , phoning the police and reporting you missing , phoning your employers , posting evil things on your social media ,
These men do NOT like losing control .