How to improve your English pronunciation by reading aloud
Listen to a short passage read by a good voice, then read the same passage aloud and check which words and sounds came out wrong. Ten minutes a day with feedback does more for your pronunciation than hours of silent reading or repeating isolated words.
Why silent reading does not fix pronunciation
You can read English well and still be hard to understand when you speak. Silent reading builds vocabulary and grammar, but the voice in your head pronounces every word the way you first guessed it. English spelling makes those guesses unreliable: though, through, tough and thought share four letters and no vowel sound.
Pronunciation is a physical skill. The mouth has to make the movement, and the ear has to hear the result. Reading aloud is the simplest way to practice both on real sentences, with natural rhythm and linking, instead of on word lists.
Listen first, then read the same passage
Start with the model. Play the passage and follow the words as they are highlighted, so every written word gets attached to its sound. On Booklern every section of every book has a speaker button, and you can click any word to listen from that word.
Then read the same passage yourself. Keep it short: one paragraph, 50 to 150 words. A short passage read three times teaches more than a chapter read once. Any book works, but dialogue and simple narration are easiest: try Alice's Adventures in Wonderland, or pick from the short books.
Get feedback you cannot give yourself
The hard part of practicing alone is that you do not hear your own mistakes. If you could, you would not make them. This is where a scoring tool earns its place. In Booklern you press the microphone beside a passage and read; each word turns green, yellow or red while you are still speaking.
Click a word afterwards and you see it split into syllables and sounds, with the weak one marked, and a plain line such as: /θ/ sounded like /s/. You can play back your own recording of that word and compare it with the correct pronunciation. After each reading you get three scores from 0 to 100: content (did you say the words that are there), pronunciation, and fluency. Pauses in the middle of a phrase are marked too, because rhythm is part of being understood. How it works has the details.
Fix sounds, not words
After a few readings a pattern appears. It is rarely fifty different problems. It is usually three or four sounds that come back in every passage: the two th sounds, the short vowel in ship against the long one in sheep, the vowel in cat, a final consonant that gets dropped. Booklern's Practice page collects them as "sounds to work on", weakest first, next to the words you mispronounced.
Work on one sound for a week. Find it in your red words, listen to the dictionary pronunciation, say the word slowly, then read the whole sentence again. A word leaves the list once you read it well, which is a small, honest reward.
A ten-minute routine
One: open the book you are reading anyway and pick the next paragraph. Two: listen to it once. Three: record yourself reading it. Four: click the red and yellow words, listen, repeat them. Five: record the same paragraph again and watch the score move. That is the whole session.
Do it daily rather than for an hour on Sunday. The day-by-day chart on the Practice page shows the trend, and the trend is what matters: a score of 70 that becomes 80 over a month is a real change in how you sound. Recording needs a free account; the audio itself is never stored, only the scores.