I'm a seasoned D&D 3e/5e DM, and I'm interested in learning how to run an old-school game. The trouble is, the 3e/5e "way" is trained into me (e.g. I'm very used to calling for skill checks to resolve things, I am used to characters having mechanical actions to take in combat other than their normal attacks, etc.). I'm concerned that if I don't shift my thinking a little bit, I will make the system feel boring and restrictive to my players.
How do I learn to run a successful old-school style game for my friends who are also used to later editions?
The appeal of the whole old school thing, to me, is the simplicity of it. I figure that having fewer rules than 3e and 5e might speed things up and also encourage a more immersive and less "gamey-feeling" playing experience. I'm not tied down to any particular OSR system, but Swords & Wizardry and Lamentations of the Flame Princess both have piqued my interest.