The above book is a great source for language to use everyday.
Also read the following book “A Guide for Parents Speaking Irish at Home”
Note a person’s brain peeks at 2.5 years of age for processing languages, and children can easily learn, 2, 3 or 4 languages (and more) at a time. You can see the results of such on YouTube with 4 and 6 year olds speaking multiple languages before ever going to school.
The more you read-up about this subject, the more success you will have. I believe the key is that you speak Irish as you would speak English to the child. Including reading stories, showing cartoons in Irish (TG4), etc. etc. There are more resources then ever before on this. You have a few choices here. Everyone speak Irish to the child and it will start speaking Irish. S/he will very quickly pick-up English when she goes to kindergarten school. Are if you want the child to be bilingual have one person always speak Irish, and the other always speak English. The child will likely used mixed language sentence to begin with, but will quickly refine that. Children that speak even more languages, often have grandparents that speak a third or fourth language to them, and then if there is a nanny with a different language, have her speak that to her. The child should get plenty of exposure to each.
It’s a once off golden opportunity to have the child learn multiple languages without ever being terrified with the words “grammar, lesson plans, etc.” so definitely go far it. I would have done so if I was ever blessed with children.
Of course, the biggest challenge will be encouraging them to maintain their language skills once they start going to school regular. As over time they can loose what they learnt without regular use. So plan to make speaking Irish, etc. a lifetime event.