How to use the cards (and how not to)
Three minutes a day is plenty. Here is the short version of what works.
The most common mistake is doing too much. These are not lessons and there is nothing to get through.
Hold the card 20–30cm from your baby's face. Closer than feels natural. If your baby is on their back and you are leaning over, that is about right.
Wait for the lock-on. The eyes will drift, then settle. That settle is what you are waiting for. Hold still while it lasts.
Stop when they look away. Looking away is not boredom or failure, it is a full working memory. A newborn might manage two cards before they are done. That is a complete session.
Two or three minutes, once or twice a day. More than that is for you, not for them.
Use them during tummy time. Propping a card in front of a baby on their front gives them a reason to lift their head, which is the actual hard work of the first few months.
What not to do
Do not test. Do not ask a nine-month-old which card is the alif. Do not run through the whole deck because you paid for the whole deck. Do not use the cards when your baby is hungry, overtired or already crying — you will get nothing, and you will both end up frustrated.
And do not worry if a week goes by and you have not touched them. The cards are a small useful thing, not an obligation.
Talk while you show them
The cards are visual, but your voice is doing at least as much work. Name what is on the card. Say the letter. Say it in whichever language comes naturally to you — the point is the sound of a parent's voice attached to a thing being looked at.
That pairing, repeated casually over months, is most of what early language acquisition actually is.