Reading comprehension strategies help students make sense of what they read. You will probably use several of them every time you plan a reading lesson. You should also consider how to teach students to use some of these strategies as they read independently. (See English Reading Comprehension for one way to do that.)
The way you introduce a reading lesson makes a huge difference in both student motivation and comprehension.
Take the time to plan an intriguing introduction that helps students see the value of learning about your topic, arouses their curiosity, and raises some of the questions the reading selection will answer.
One way to introduce the subject is with an anticipation guide: Write a number of statements based on the text (making some of them false.) Then have students react to the statements, choosing which they think are true and which are false.
Students need enough background knowledge to grasp the author's main points and to connect what they read with what they already understand.
A quick discussion about the subject before reading can “activate students’ prior knowledge” (help them remember what they already know about the subject and its vocabulary). It also tells you what students know (and don't know).
Asking younger students (individually or as a class) to make a KWL chart (what they already Know, Want to learn, and—after reading—have Learned) can focus their attention on what they would like to get from the reading, as well as letting you know if you need to do some pre-teaching.
A short explanation may provide enough background to help them benefit from the reading. If not, do you have access to materials (in class or online) that would enable them to make sense of it? If you're able to rearrange the lesson and postpone the reading until after they get a little background, it might prove far more useful to them.
I was impressed with this education researcher's video on the need for background knowledge.
While planning the lesson, look through the reading selection for any words your students may not know that are essential to understanding it (as well as any with new meanings that might confuse them.) If the word is not common, you can just give them a quick explanation or synonym.
If a word is important for understanding the story or article, can you help students break it apart to approach the meaning through its root and affixes, if they are familiar? Are there context clues that can help them figure out its meaning?
If it’s a word that they will need often, teach it in more depth, with examples (and possibly non-examples—how it isn’t used), synonyms (and when each is more appropriate, if they differ in connotations or register) and antonyms, etc. Ask them to use the words you have taught in the post-reading activities.
When you first pass out the reading selection, ask students to scan the title, introduction or first paragraph, headings, and any illustrations or charts. Have them make predictions about its topic and main ideas. (This will also help them focus on the content as they read, to see if their predictions were correct.)
Remind students to focus on finding the information they need, or answers to the questions or true/false if you gave them some in the beginning.
Encourage them to keep reading when possible rather than break their concentration by stopping to look up every unknown word. (It will help if you have pre-taught the most important vocabulary and if students have some understanding of word decoding and context clues. (They might be worth a special lesson. See Reading Skills.)
You may also want to encourage them to note the main ideas or words they want to look up or discuss later.
There are many ways to check comprehension: a class discussion, comprehension questions or a quiz, group or individual summaries or even drawings of the main idea. Be sure to ask some questions that require critical thinking and a personal response to the ideas expressed, not just 5-W factual questions (who, what, where, etc.).
Using several related readings can provide great opportunities for comparisons, a more critical examination of the author’s point of view and possible biases, and vocabulary and content reinforcement.
For more ideas for teaching with reading comprehension strategies, especially some excellent comprehension questions, see this Colorin Colorado article.
Reading comprehension strategies and skills can help students a great deal, but they're not a magic bullet. As you work with your students you will learn the areas in which they need extra help and can plan lessons targeting their weaknesses and supporting their strengths.