Frost Dragons; 3m an hour. Regular anti-fires are RS gold sufficient, but you might need to consume food. Try using a knife. The biggest issue in this technique is that you need 85 Dungeoneering to use it and some magic notepaper.
Kill the monsters of QBD or ascension (gladii, Roarii) until you are able to afford drygores. Continuing with warbands until 96 Herblore is wise as well.
Join a nex or continue QBD until your prayer level is 95 or prayer, 96 Herblore or tier 90 equipment is attained. Skills-Some people don’t like killing the same things repeatedly, so I thought I’d include this. Runecrafting. Go to the Runespan at level 1, keep training until the level 59 of Runecrafting. You can create two cosmic runes out of the abyss at level 59. This can be an acceleration of up to 2m/hour. At 82, it is possible to craft double astral runes. Based on GE costs, it could be better than cosmics. At 91, you can create double natures. You can also look up GE prices to determine the best price.
Herblore. Training normally, or daily warbands to a certain level. Make incomplete potion (water and a plant) and then sell them. Crafting. Shades of Morton. Restore the temple and create sacred oil by using olive oil and the sacred flame on world 88. ~1m per hour and very AFK.
Miscellania Management - Complete both the quests and then enter 10m. Expect about 160% returns if using proper allocation (I do mahogany logs). Player-owned Ports - You can earn millions of dollars a week using about five minutes of work per day. To start Ports or make products, you'll be required to be doing this for about one year.
Shop buying - purchase shop materials such as feathers, broad arrowheads yakhids, chocolate bars or battlestaffs. Kill Hill Giants in the Edgeville resource dungeon. Take the bones and the limpwurt root.
Use the keys that are muddy through the Lava Maze. Take only the important stuff. This is the best method to earn f2p. I'm estimating 400k/hr but it takes a while to collect dirty keys. Gem bags are the most efficient choice for the highest efficiency. Mine adamant ore. I like to mine this at the hobgoblin mining location. Wear full batwing, shield and food isn't necessary. Hop worlds. It's not common to see PKers in the area. Superheating can also be done through mining coal. This will prolong your travel time however I'm not convinced that buy RuneScape gold it's more efficient. 70 mining is required, 70 smithing if superheating.