I'm getting close to 30 now, and I have just hit my 19th mastery page... I'm really struggling with what to use as a "standard esque" page that fits certain roles. Currently I am using 1 page for 1-3 champs.
Ideally, what i want is a page for each of the following:
Mid ap
mid ad
top ap
top ad
Jungle ap
Jungle ad
Support
Anyone able to point me in the right direction? Google has thrown a lot of confusing information out there.
Mastery pages are things that you can change on the fly.
Generally, Mid AP pages will want the CDR column fully with a few points in the side things, like the one that increases minion damage, the one that increases damage below 50%, the one that grants health and mana on kill/assist and the one that increases damage done and taken. You will want Spellblade and 3/3 points in the armor/magic pen. Obviously you want a point in the last one in the tree. After that, you have 9 points to choose whether you want defenses (basic attack reduction, health regen, health) or utility (mana regen, the biscuits, move speed, recall time, summoner spells).
AD will want the AS column fully OR the CDR and then the column under AS. You don't get spellblade, but you basically go the same as AP mid page. You'll usually want to go defenses on AD mids, but some mana ADs (Talon) could use the mana regen.
Junglers will either want to go 21/9/0 or 9/21/0 usually. You probably want the damage reduction to monsters. On MOST junglers, AS is more useful than CDR. The rare exception is Fiddlesticks, who doesn't AA. After that tier, you want whichever offensive stat you need (AD or AP) and probably the damage to minion/monster increase. Defensive tree is matchup dependent usually and a lot of preference calls.
Support wants the gold giving masteries and probably the level mastery in support tree. You can opt to go mostly AP page on heavy poke supports. Support tree pretty preferential as well.