Divination is essentially,using items or objects to determine possible future events and outcomes. You can do this with runes, tarot cards, candle wax, etc. The medium is entirely up to you.
I persoanlly use tarot, ceromancy, and runes.
Scrying is probably one of the easier methods. You can use smoke, a mirror, crystals or water as a medium for this. An easy way is to ask a question and focus on incense smoke and see what shapes it takes. The shapes can then be decphired later to determine the outcome of your question(s).
I added some links below that you might find helpful.
One of them is actually a link to an article on the topic here on the site. It's brief but has some good info.