Recently I started helping children in the reception class (coming up to 5 and just turned 5) with their letters and it is so rewarding - just wish I had done this years ago!
Four of the little boys have been struggling recognising the letters so have introduced a game exercise rather than words as such. Their teacher provided me with a box of all the letters of the alphabet on cards plus various pictures also on cards. We played a form of snap.
Each boy was given one of the cards showing a letter. I turned all the picture cards upwards showing the picture and asked them to match the letter card with the picture. I got them to pronounce their letter and also to see whether there were any other picture cards with that same letter.
Then I turned the picture cards upside down on the table and put the letter cards face upwards as well. Each boy had to pick one of the cards facing downwards, tell me what it was and to match it with one of the letters. Each time they did this, I got them to tell me what the letter was and to say it repeatedly.
We also did some other guessing using the letters. They did so well that each of them was given a prize. At the end, one of the little boys actually thanked me for the game and he was one of the shyest.
What I am therefore suggesting is if you make this business of reading a game rather than actually reading, you may be surprised at how your child will improve.
Letters b and d tend to get mixed up but eventually, your child will realise which is which simply by the sound of the word. Lots of praise when your child does well will go a long way - again make even this a game. Say five or ten "well-done" will result in a small prize.
At the end of all this, you want your child to enjoy books and reading so the simpler methods of teaching seem to be the solution. Bearing in mind I am not a teacher but just a grandma, the results of my efforts with these children have been remarkable.
Using the school books as a format, print some of the shorter words, cut them out, give your child say ten of them, get the child to say the letters phonically and try to combine all of them into the word. When these selection has been done, do another selection and work at them on a daily basis.
You will need an abundance of patience but it really is so worthwhile in the long run. Keep reading books, get your child to repeat the words with you as well.
Good luck!