Lissandra is a champion who doesn't rely on her burst too much.
She is a great asset and a plays a huge part in late game team battles.
A lot of her spells are closer range than most mages so she needs to have some survivability in lane such as armor and magic resist.
I refer to Lissandra as the area of effect queen she can quickly do lots of damage to multiple opponents and her crowd control abilities are extremely helpful for kiting and team battles.

These are just the basic runes I use but for more ap damage exchanging the magic resist glyphs for scaling ap glyphs will give you more damage.
I mainly use a little attack damage on my mage builds for minion and champion last hits cause I hate when you hit a minion or champ and don't have that extra damage on your basic attack to get the kill
I also use the scaling armor and magic resist runes on Lissandra because when she has to close in on an enemy she will need to survive, as well as in ganks she will need to survive long enough to E out of the battle

Lissandras spells consist of burst and crowd control abilities when used correctly and swiftly she can easily lock any opponent in their tracks

Q- Ice shard allows for a quick burst of damage and on hit scatters into a cone and goes further than the point of impact this allows you to keep a fair distance in lane and still grants easy harass by the usage of minions. This is also a great kiting tool due to is slow effect. It allows you to keep some distance between you and an enemy in pursuit by spamming this ability. all in all it has a low cooldown so you can use it often to harass and farm.

W- Ring of Frost is a great tool Lissandra uses to lock enemies in place it is a root so ranged champions and spellcasters can still attack while rooted. It is also a great escape technique from charging champions like Rammus or Hecarim when they are coming at you full force you can easily lock them in place for a second to give you a chance to get away. With a fairly small cast radius that eminates from Lissandra herself it is a good tool for last hit farming or just quick burst damage to enemies. You must remember though since it has a small cast radius this puts Lissandra in the heat of battle so she will need some form of sustain to continue. This ability is also very usefull in team fights

E- Glacial path Is a slow moving long ranged attack that has the highest base damage of all of Lissandra's abilities. This ability also offers a teleport for Lissandra depending on the location of the claw in glacial path. This teleport is great for initiating or fleeing from battle. The claw has a wide cast range and a fairly long range to boot so its very easy to hit multiple champions. Though it is slow it is Lissandra's longest ranged spell and can be used to harass at long distances or sufficient damage at close range. The teleport it offers is a great way to fool your opponent me spontaneous with it so they can never truly tell if your going to teleport or not. That all be said this spell does have a longer cooldown so be sure to save it early game if you want to be more aggressive cause if you extend to far your easy prey for jungle ganks but having this spell active at any time cuts that enemy gank potential.

R- Frozen Tomb is Lissandras ult has Such potential for amazing plays. First it stuns and locks one enemy in place then extends to deal damage to all surrounding enemies. It does not root or stun any other enemies hit other than the first target. But if built with high AP this ult can make or break a team battle and combining it with her passive gives you more mana for high damage plays. Secondly This ult can be cast on Lissandra herself This makes her invicible to all damage for a few seconds but she cannot cast any other spells while in the ice but the ult still extends to do damage to all surrounding enemies. This is a great tool for turret diving, or just initiating a team fight.

Pros

[*] Decent burst damage
[*] High crowd control and area of effect spells

Cons

[*] Can be difficult to master
[*] slower than some champions
[*] low cast radius on some spells

Lissandra can easily wipe out waves and waves of minions. Lissandra does also have jungle potential due to her crowd control and her gank potential with her E- Glacial Path.

Lissandra on any team is essential to team battles. Her area of effect spells and her crown control can easily turn team fights. Be safe though she isn't terribly squishy but depending on your build she can be. Also people will target you first so starting with her ult cast on herself can keep you safe and give time for your team to jump in.