Deciding what spell to apply Blaze first with is a very important factor when engaging the enemy.
If you are able to cast your spells quickly, Brand can actually be very effective at close range. Close proximity allows Sear to hit a lot easier, so if Conflagration is used just before the missile hits, the stun is very reliable.
An effective combo to clear minion waves is to use Sear on a minion positioned close to the middle of the wave, Conflagration the Blazed minion, then Pillar of Flame all Blazed minions to deal increased damage.
A great time to use Brand'sPyroclasm is when two enemy champions are standing close to each other.
By using Pyroclasm's bounce, Brand can cast on a nearby enemy and subsequently hit, or even kill, a weakened enemy Champion who would otherwise be out of range.
Pyroclasm does not prioritize Champions unless hitting a target afflicted with Blaze, so avoid casting it when close to minions or neutral monsters.
Remember that Brand, like LeBlanc, is primarily a combo champion. Using one spell at a time is a huge waste of damage potential, and it's better to stay at the back of the fight while waiting for your cooldowns on one of your 3 main abilities.
When you are focused on one champion, your combo should usually be Conflagration, Sear, then Pillar of Flame. This combo allows Sear to stun, ensuring the enemy will be in the AoE for Pillar of Flame and offering little time for them to retaliate. If you are fast enough, you may be able to cast Sear first and, while the missile is on its way to the target, hit them with Conflagration before it connects and throw down Pillar of Flame.
When you want to do maximum damage to multiple enemies, pick a target, cast Sear at them, after Blaze is applied, cast Conflagration to hit multiple targets and apply Blaze to each one, then finish with Pillar of Flame. This combo, if all hits connect, can do huge AoE damage. If your Pyroclasm is off cooldown, throw it out as soon as enemies are grouped together enough.
Brand makes an excellent choice as a solo laner as the AoE, combo-effectiveness of his spells allows him to farm minions quite well and keep opponents out of exp range and from last-hitting minions. His high mana cost, however, means frequent trips back to base. Be wary of being caught on low mana, because his anti-champion combo is relatively expensive.
Brand has a very effective escape mechanism. Inflict Blaze by using Conflagration, and then stun with Sear while running. Do not cast Pillar of Flame as it has a longer spellcast animation, which isn't beneficial when trying to escape.
Getting every one of those items will sacrifice a great deal of other stats like health and resistances, so getting all 3 isn't recommended.
Abyssal Scepter is another item which can accomplish the same effect for Brand, though the effect is less reliable for him so it should only be considered if you find yourself in need of magic resistance.
Rylai's Crystal Scepter will be very effective for Brand since he deals a lot of AoE damage, and since the proc effect adds slows to his abilities. It also keeps his enemies in range of his skill shots and helps slow champions to make it harder to avoid the bounces on his ultimate. It even adds to his passive, effectively giving everyone you hit a 4s slow even after you stop casting.
Will of the Ancients is notably effective on Brand since all of his spells deal high AoE magical damage, which all proc spell vamp. Note that spell vamp only has a 50% effect with AoE spells and does work with his passive Blaze
Survivability items are essential for Brand due to his very low health and defensive stats. Even a fed Brand can be taken down fairly quickly and/or easily if he does not accomodate for his lack of survivability.
Athene's Unholy Grail is a very useful item for Brand, granting him a decent chunk of ability power and cooldown reduction, while also granting him the mana regen to spam his spells significantly more frequently. An early Chalice of Harmony is a highly effective purchase, offering unparalleled mana regeneration for a very low cost.
Brand has no escapes, and, to successfully kite an opponent, must apply Blaze then successfully land Sear. Play aggressively early game and target him at any time he overextends.
When playing against Brand, remember that he is a combo-based champion. Interrupting his cast flow is detrimental to his damage output.
Brand is countered in this aspect by stuns and silences, and, in careful appilcation, can be very effective counters during team fights.
When he is at a distance, Sear is easy to dodge, but be careful about getting near him in a fight if you are squishy.
Be careful about facing Brand 1v1 or 2v1 (with Brand being the one). Brand's 1v1 damage output is still great despite having AoE spells, he has a 2 second stun from Sear while the target is Blaze. 2v1 would be even worse after he hits level 6, as his ultimate will be able to do tremendous damage to you and your teammate.
When fighting against Brand in a team fight, try not to stick close to your teammates. Brand'sAoEs spells are rather small but very deadly.
When Blaze is applied to you, be very careful about getting within Brand's range, especially if he can hit you with Sear, as this opens you up to a lot of burst damage.
During laning, be careful about being on the wrong side of your minions when against Brand. With his full combo, he can deal a large amount of damage while stunning you to prevent retaliation.
Your team should scatter to avoid taking massive AoE damage from Brand, especially after he casts Pyroclasm.
Pyroclasm does not focus champions unless applied with Blaze, so try to pass it off onto a group of minions or jungle monsters.
A Banshee's Veil is a great item to counter him. While it won't completely negate the damage Brand does, it will make it harder for him to combo off properly.