Perhaps first getting her aqquainted with basics would be a most prudent task to complete.
Basics such as:
1.What the pokemon series is as a whole (Basically the objective of the game/plot)
2.Perhaps THE most significant implement of RPGs such as pokemon,is level/EXP gain.However if she is a novice at the concept of RPGs,it is of significant importance that you explain leveling,How to gain EXP in order to level up,You will also need to describe to her how both her pokemon and the enemies pokemon affect EXP gain.
3.Explain the stats and how they are utilized throughout the playthrough and what pokemon are ideal for said stat.
I.E.-(* = Best)
Attack(atk) - Salamence*,Blaziken,Metagross*,Absol
Defense(def) - Metagross*,Sandslash,Altaria,Torkoal,Duclops
Special Attack (sp.atk) - Alakazam* (Link trade),Gardevoir,Gengar(Link trade)
Special Defense (Sp.Def) - Gardevoir,Blissey* (link trade),Kecleon,dusclops,Tentacruel
Speed(Spd) - Sceptile,Ninjask*,Raichu
All-Around (decent stats all around) - Swampert,Flygon,Salamence,Metagross
3.Describe the varying Battle tactics (Simplistic craft such as Catching,switching,leveling,item usage,as well as attacking)
4.Detail the varying attributes of abilities and their effects on battle
5.What pokemon are decent at the beginning with said stats and abilities,such as Starter,tentacool,ralts,Ninjask.
6.Perhaps detailing items that could assist her substantially in the beginning would be of great assistance.A key item is the Experience Share,an item which DistributesEXP evenly to one pokemon in the party.Could prove useful due to her beginning the series.
7.Type matchups are also significant to detail.Matchups such as follows
Fire>Grass
Grass>Water
Water>Fire
Electric>Water
ETC....
Multitypes such as Nidoqueen,whom sports a Ground/Poison Typing are also impartial to know of.As a majority of the pokemon within emerald.
8.Difference of special and physical attacks.
Special attacks target special defense whilst Physical attacks target Defense.Assuredly it would also be useful to note elemental weaknesses coupled with these attacks,to increase damage output.
However,you will have to explain this part as she delves further into the game.
I believe all the information provided should help ease her in her runthrough and should assist her into more advanced concepts such as status moves and tactics using them to EV training.As she continues,You will need to assist her further if she is willing to get into these concepts.