I just did a google search on "how to catch summer trout" and I found complete garbage. Most of the articles describe that unless you have perfect conditions its impossible. Here are the facts.
Trout burn a huge amount of calories swimming against the current.
Why do they swim in the current?:
1. Its safe. Its hard for predators to see into a fast moving current.
2. It provides the highly oxygenated water that trout need to survive.
Trout are not watching their weight. They are eating to survive. If they see something that looks like food they are going to eat it.
I think where these articles I read fail is that they don't draw the connection between how outside factors like temperature may change the habits of trout.
Here is the best rule for Trout. The best water to fish is where you can't see anything.
If you look in a slow moving clear area and you see fish in a stationary position pointing upstream they are not trout. Inexperienced anglers spent hours trying to get "suckers" to bite trout lures. Suckers look like trout in the water and they are found in slow moving water. You will not find trout there.
If you see the fish, leave them alone, they are not trout. I would rather catch nothing than a sucker. They are a disgusting, disgusting fish.
You need to find fast water where you can't see the bottom and the front of deep pools. Not the back or middle of deep pools. It must be the front.
Summer Trout are more difficult to find. There are less places for them to hide, the water is warmer and they are just less of them.
If a trout stream in August has 10% of the Trout it had in April, then you can see how its tough fishing.
You just have to be selective on where you fish and be prepared to walk.
Do not use live bait in the summer. Its just too hot.