You can use a brief and simple tafsīr, such as Tafsīr As-Sa‘di (may Allāh have mercy on him) or similar works. There is also a summarised tafsīr called At-Tafsī

There is also a tafsīr of Juz ‘Amma for the general public by Shaykh Ibn ‘Uthaymeen, which is beneficial, though it is more detailed. Also, the caller to Allāh should pay attention to warning people about the widespread wrongdoings among them. There are many common wrong practices that need to be addressed. Even if he reminds them of just one issue each day, that would be good. Our brother Abu ‘Abdillah Ṭāriq Al-Waleedi compiled a booklet on this subject of about two hundred pages. He arranged it into thirty lessons. In each lesson, he discusses a major sin or a forbidden act that is common among Muslims. He wrote it especially for brothers who go out for da‘wah during Ramaḍān. Even if someone cannot read all of it, he can summarise parts of it and present them. This is also an important part of teaching. Likewise, he should teach them the rulings related to fasting, Tarāweeḥ, zakāh, i‘tikāf, and other matters they need for their worship—even if only in a brief and simple way. --- Perfecting the Qur'ān The one who goes out for da‘wah should also take care to perfect his recitation of the Qur'ān. When he leads people in prayer, he should review and master what he plans to recite. This makes the prayer easier and more beloved to the people. If the imam recites the Qur'ān correctly and beautifully, people will love the prayer more. And people feel at ease because of that. There is great benefit in this—leading people in prayer with beautiful recitation of the Qur'ān is itself a great form of da‘wah. A good prayer with proper Qur'ān recitation draws people closer to Allāh and inspires them. --- Wisdom in Da‘wah I also advise the brothers who go out for da‘wah to deal with people with wisdom. They should prioritise what is most important and place everything in its proper place according to the Sharī‘ah. Sometimes a caller may postpone certain matters for the sake of greater benefit at a more suitable time. Our Shaykh Yahya (may Allāh preserve him) used to advise brothers going out for da‘wah with this principle. He would advise that some actions, though allowed, might be misinterpreted by ordinary people and give a wrong impression of the da‘wah. Enemies of the da‘wah may use it to criticise the effort of Ahlus-Sunnah. Therefore, these actions should be delayed or handled carefully, while other Sunnah practices are followed instead. For example, praying while wearing sandals. In Dammaj, we pray in sandals. But if a student goes to another village and prays in sandals there, it may be misunderstood and reflect poorly. The matter is flexible—both praying barefoot and in sandals are allowed. The Prophet ﷺ prayed both ways. So do not insist on one side and ignore many other important matters. If you have the ability to manage both, do so. Following the Sunnah while protecting the da‘wah is good. If you are unable to do everything exactly, and there are other Sunnah practices of the same type, do what is suitable for that time and place so that the matter becomes easier. However, if there is a Sunnah that must be performed, and the choice is between doing the Sunnah or doing something that is a bid‘ah, then you should perform the Sunnah, teach people about it, and be patient with them in doing so. ---- Reviving Neglected Sunnah Practices If you want to revive a Sunnah that has been forgotten by people, the best approach is first to teach them about it. Explain the Sunnah clearly, show them that the Prophet ﷺ used to do it, and cite relevant ḥadīths and the opinions of the scholars. After teaching them, then you perform it yourself. Once they have been taught, many people will accept it, In-shā-Allāh.