I've been trying to start a project, but I don't understand genetics too well. Is there anyone who knows more about this and can help?

Removed.

this guide post may help also

For those starting out on project breeding, I very highly recommend reading Xavion's 6v breeding guide. It is good information no matter how many visibles you are planning to breed to.

If you're looking for quick genetic specifics, Sylestia uses Mendelian genetics which assumes that each trait slot has two markers and every baby gets one marker from each parent. To differentiate these markers and to determine their dominance, genes and mutations each have a letter designation. Higher in the alphabet means that trait is more dominant than other traits in the same slot. Simple first example:



If I breed Arrow's Flight and her mate Arrow's Fall:

Arrow's Fall:
Gene One: (AA) Ferret
Gene Two: (BB) Petals
Gene Three: (CC) Lucky Runes
Mutation One: (CC) Wispy Tail
Mutation Two: (BB) Ram Horns
Mutation Three: (AA) Chibi Wings

Arrow's Flight:
Gene One: (AA) Ferret
Gene Two: (BB) Petals
Gene Three: (CC) Lucky Runes
Mutation One: (CC) Wispy Tail
Mutation Two: (BB) Ram Horns
Mutation Three: (AA) Chibi Wings

Because they have 100% identical traits, all of their offspring will only have those traits. There is no way for them to have any other traits ever because both parents only have the same traits to give their offspring.

More complicated example:



Malfurion:
Gene One: (HH) Cross Fox
Gene Two: (BB) Fallow Deer
Gene Three: (II) Star Runes
Mutation One: (AA) Tri Tails
Mutation Two: (CC) Leaf Trappings
Mutation Three: (DD) Glowlight Wings

Buttercup:
Gene One: (DD) Back Stripes
Gene Two: (EE) Dapple
Gene Three: (EE) Lucky Runes
Mutation One: (AA) Tri Tails
Mutation Two: (EE) Ball Mask
Mutation Three: (GG) Feathered Wings (Stripes)

Because this pair of 6 visible pets each has only one trait in each slot (example: HH Cross Fox), all of their offspring will come out looking like this:



Gene One: (DH) Back Stripes
Gene Two: (BE) Fallow Deer
Gene Three: (EI) Lucky Runes
Mutation One: (AA) Tri Tails
Mutation Two: (CE) Leaf Trappings
Mutation Three: (DG) Glowlight Wings

Each of the more recessive traits are now called 'hiddens' by the community, as these traits that you can't see can now be passed down to offspring in a 50/50 chance with the visibly expressed traits. Hiddens can only be seen on a pet once they have been genetically tested (otherwise it looks like they have only the more dominant trait). However, even if the pet is not tested, that pet would still have its hiddens and has the same 50% chance of passing it to its offspring.




Very complicated example:



Breeding Gold Class and Golden Tapestry:

Gold Class:
Gene One: (CH) Paint
Gene Two: (BC) Faded Scales
Gene Three: (BB) Striped Mane
Mutation One: (AJ) Carousel
Mutation Two: (HJ) Whiskered Dragon Mane
Mutation Three: (DE) Butterfly Wings

Golden Tapestry:
Gene One: (GK) Abstract
Gene Two: (CH) Turtle Shell Scales
Gene Three: (BC) Striped Mane
Mutation One: (AO) Carousel
Mutation Two: (BG) Unicorn Horn
Mutation Three: (CE) Stardust Wings

Both of these pets have multiple hidden traits and so the possibilities for the offspring become far more complicated.

Gene One: CG Paint, CK Paint, GH Abstract, or HK Lucky Runes
Gene Two: BC Faded Scales, BH Faded Scales, CC Turtle Shell Scales, or CH Turtle Shell Scales
Gene Three: BB Striped Mane or BC Striped Mane
Mutation One: AA Carousel, AO Carousel, AJ Carousel, of JO Dragon Scales
Mutation Two: BH Unicorn Horn, GH Nebula Mane, BJ Unicorn Horn, or GJ Nebula Mane
Mutation Three: CD Stardust Wings, DE Butterfly Wings, CE Stardust Wings, or EE Enchanted Butterflies



Which trait is expressed will always be determined by alphabetical order, except for one case: N. In sylestia, N stands for no trait and is dominant to every other trait. If there is a slot that has NA for example, it means that this pet only has one marker instead of two, so it can't express a trait visibly in that spot. However, it carries that trait and can pass it down to a baby. If both parents have NA in a slot, as an example, the baby could get NN, NA, or AA in that slot (25%, 50%, and 25% chance respectively).

Visibly on a pet's profile, if the pet is tested, visible traits that have only one trait possibility for inheritance are blue, hidden traits which have two possibilities for inheritance are purple, and carried traits which have half a chance of inheritance are green.

Hopefully that wasn't too confusing. Xavion does a much better job of explaining everything XD

(NeonNy, I have a desperate need to know, where you got the '33%' come from? ("If bred with a pet who is holding a different trait, there is a 50% chance that trait will be passed on, or 33% if the other pet has a visible and hidden trait"))

I think I should correct a few things. Sylestia uses punnet squares...so...you know, 7th grade science.
The closer the letter is to A, the more dominant it is. The closer to Z, the less dominant. Just focusing on that.

"If that pet is bred with others who have no genes carried in that slot"
Just want to clarify that this is only for a Visible x Nothing (NN). With a Carried x Nothing, there is a 50% chance of having the same carry as the Carried parent, and a 50% chance of Nothing.

"Gene three is a carried trait, if bred with a pet who has the same trait (Visible, hidden or carried) it will be passed on as visible."
I will use the G3 example of the earlier pet. If bred to a male with carried (NA) Advanced Runes through (JJ) Rainbow Advanced Runes, the square will look like this:

As you can see, there is a 25% chance of having nothing in that trait, a 25% of carried Glowing Stripes (NK), a 25% of carried Rainbow Advanced Runes (NJ), and a 25% chance of visible Rainbow Advanced Runes
(JK) with recessive Glowing Stripes. In this scenario, visible Glowing Stripes is impossible.
If the father also has carried Glowing Stripes (NK) or perhaps Valentine's Lace (LL):

25% nothing, 50% carried Glowing Stripes (NK), 25% visible Glowing Stripes (KK) (or (KL) if Valentine Lace). These are the only scenarios in which the offspring will have visible Glowing Stripes (it's quite a low-dominance gene).

"If the other pet you are breeding with has either the visible, hidden or carried trait of the same gene, it will always be passed onto the offspring."
Not always, for carried, see above. 25% chance of nothing.

"(If bred with a pet who is holding a different trait, there is a 50% chance that trait will be passed on, or 33% if the other pet has a visible and hidden trait)"
If the other trait is carried, refer to the above charts to see whether it is higher or lower dominance. I don't know where the 33% is from, that doesn't work with single-gene punnet squares. I second Scath in wanting to know what the 33% is.
Carried Glowing Stripes (NK) x Visible Advanced Runes (AL) with recessive Valentine's Lace:

25% of carried Advanced Runes (NA), 25% of carried Valentine's Lace (NL), 25% visible Advanced Runes (AK) with recessive Glowing Stripes, and 25% visible Glowing Stripes (KL) with recessive Valentine's Lace.