Having a mnemonic helps me with routine everyday things, though one-time things require the “attach keys or block door” method.
What I have settled on for routine items is a numbered list. Nothing complicated to remember. Just which item is which number.
When I get ready to leave my house, or stand up to leave work, it goes like this counting in my head:
1, 2: work phone and personal phone in one pocket
3, 4: wallet and keys in the other pocket
5, 6: watch on my left wrist and water bottle in my right hand
[7, 8]: if necessary: wireless earbuds and backpack
Plus at work, I have a strict rule that I cannot put my keys anywhere but my pocket. My fob to get in the building is on my key chain, and after the second time I locked myself out I made the rule. If I do take my keys out of my pocket to clip/unclip something like a USB flash drive or nail clippers, the keys stay in my hand until they go back into the pocket.