"Increase skillshot width by" - This is the amount that the script adds to each skillshot's radius to help make dodging more accurate. As an example, Karthus's Q radius is 140. If you set this to 10, it will dodge in a circle with a radius of 150 instead of 140.
"Delay for skillshots in the FoW" - This is the number of game ticks the script will wait before adding a skillshot from the fog of war. Also includes certain other skillshots, such as Vel'Koz's second Q activation. Increase this if you have issues with skillshots appearing in random directions from the fog of war (or, again, those certain skillshots).
"Dodge skillshots" - Whether the script should dodge skillshots or not.
"Dodge CC only spells" - This hotkey is for dodging only spells that cause CC (any type of CC; slows, stuns, silences, etc.).
"Dodge CC only spells toggle" - This hotkey toggles the previous setting on or off.
"Dash to dodge spells" - Whether or not the script should use dash abilities to dodge skillshots.
"Always dash towards your mouse" - Whether the script should use your mouse position or it's calculated position for dashing spells.
"Use dashes below what % HP" - What percentage of your HP bar the script should begin dashing under. If you put 50%, for example, it won't dash any spells unless you're under 50% HP.
"Always try to dodge line skillshots" - This will force the script to dodge each skillshot, even if the skillshot cannot be dodged.
"Flash to dodge dangerous spells" - Whether or not the script should use Flash to dodge dangerous abilities (eg. Annie ult). This setting has very inhuman reaction times; caution while using it.
"Draw skillshots" - Whether the script should draw skillshots or not.
"Reset dodge" - This hotkey forces the script to stop dodging and "forgets" all current skillshots.
"Allow use of 0 cast time spells" - Whether or not the script should block use of spells that do not interrupt movement (eg. Syndra's Q and W) while dodging skillshots.
"Use 0 cast time spells with self CC" - Very similar to the previous option, it applies only to 0 cast time spells that also CC yourself (eg. Vi's Q).
"Free users movement block" - Whether or not you're using movement block for free users.
"Use old drawing" - Use the simple line drawing; I suggest using this if the rectangles cause the screen to become too cluttered.