You should have almost finished pruning your apple and pear trees by now, but here a few tips.
1. Your best apples grow on 2 and 3 year old wood. Each year's growth is separated by a ring on the wood
In this photo you can see the ring where the 2 forks of 1 year old wood branch from the 2yo wood, and you can see the fruit buds (the fat ones) which will produce fruit next season.
2. Therefore, on your branch, you need to have 1yo wood (for fruit in 2 years time - 2019), as well as 2yo wood for fruit for next year. Ideally you have approximately 1/3 1yo, 2yo and 3yo wood to ensure good apples next year and a good supply in years to come.
3. When cutting your branches, don't cut 1yo wood in the middle. You can cut 2 and 3 year old wood anywhere, and the direction of the bud nearest to your cut will direct where the branch will grow. However, 1yo wood doesn't grow if cut...it just stays stagnant for a year. If you don't want it, cut it off completely, or leave it alone until next year.