Verse 2.22.5

सर्वे स्वरा घोषवन्तो बलवन्तो वक्तव्या इन्द्रे बलं ददानीति सर्व ऊष्माणोऽग्रस्ता अनिरस्ता विवृता वक्तव्याः प्रजापतेरात्मानं परिददानीति सर्वे स्पर्शा लेशेनानभिनिहिता वक्तव्या मृत्योरात्मानं परिहराणीति ॥ २.२२.५ ॥
॥ इति द्वाविंशः खण्डः ॥

sarve svarā ghoṣavanto balavanto vaktavyā indre balaṃ dadānīti sarva ūṣmāṇo'grastā anirastā vivṛtā vaktavyāḥ prajāpaterātmānaṃ paridadānīti sarve sparśā leśenānabhinihitā vaktavyā mṛtyorātmānaṃ pariharāṇīti || 2.22.5 ||
|| iti dvāviṃśaḥ khaṇḍaḥ ||

5. Each vowel should be articulated clearly and powerfully, [and while doing so, you should think,] ‘I will give some of my strength to Indra.’ The sibilants also should be uttered fully and distinctly, without sounding as if you are swallowing part of them or spitting them out. [While uttering them, you should think,] ‘I surrender myself to Prajāpati.’ Then each of the consonants also should be uttered separately and clearly, [and while doing so, you should think,] ‘I will save myself from death’.

Word-for-word explanation:

Sarve svarāḥ, all the vowels; ghoṣavantaḥ balavantaḥ, clearly and powerfully; vaktavyāḥ, articulated; indre balam dadāni iti, [say to yourself] I have to give strength to Indra [as if you are stronger than Indra and can afford to give him some of your strength]; sarve ūṣmāṇaḥ, all the sibilants; agrastaḥ, clearly uttered [i.e., no part of the letter left within the mouth, as if you are swallowing it]; anirastāḥ, not uttering the letter as if you are throwing it out of your mouth; vivṛtāḥ vaktavyāḥ, clearly expressed; prajāpateḥ ātmānam paridadāni iti, I surrender myself to Prajāpati; sarve sparśāḥ leśena anabhinihitāḥ vaktavyāḥ, each of the consonants should be uttered separately and distinctly; mṛtyoḥ ātmānam pariharāṇi iti, [while thinking] I save myself from Death. Iti dvāviṃśaḥ khaṇḍaḥ, here ends the twenty-second section.

Commentary:

It is important that when we recite a hymn, we recite the vowels, consonants, and the sibilants clearly and loudly. Care has to be taken that no two letters get mixed up, or that any part of a letter remains inside the mouth or seems to be spat out.

Here it is said that the vowels are to be pronounced powerfully and that you should pray to Indra while singing, offering him some of your strength. This suggests that you feel very strong, as if you are stronger than Indra. You should also try to surrender yourself to Prajāpati while singing. You will then attain immortality.

Section Twenty-Three