THIS ONLY APPLIES TO NON-PVP CONTENT, BUT DO IT ANYWAYS
Due to the QOL update today, every single weapon is defaulted to attack. The easiest way to do this, is to go to a bank and equip ALL weapons you plan on using in the future and set it to the strength option so you don't accidentally get unwanted attack/defence exp. Once you make the change to your desired style, it will remember it for that weapon from that point onwards (supposedly)
Make sure you are changing your style for when you have no weapon equipped as well.
Some other things you may forget:
- F2P (Scim and maple short)
- Ancient Mace
- Fun/Holiday items
- +1 items you don't use often
- Skilling Items (D axe, D pic, D harpoon, etc)
If you already did get unwanted xp, there is a thread on official runescape forums somewhere where you can post and get the xp revereted. (It only applies to unwanted xp gained today)