Asalamualeikum warahmahtullahu wabarakat
A strong beautiful and clear voice during Quran recitation is one thing a lot of Muslims admire and wish to have especially when Bukhari and Muslim reported from the hadith of Abu Hurayrah(may Allah be pleased with him) that "" Allah does not listen to anything (more approvingly) as he listens to prophet reciting loudly the Quran in a sweet voice, Al Hakim also reported from the hadith of All Bara Ibn Azib that the messenger of Allah (peace be upon him) said : Beautify the Quran with your voices, for sweet voice increases the beauty of the Quran
How to improve your voice during recitation;
1)Recite the Quran from time to time
2) Try as much as possible to apply the rules of tajweed during recitation
3)Drink lots of water to keep your vocal cord moist
4)Drink hot teas such as green tea or lemon tea to help fight against mucus
5) Once in a day, gargle salt water
6)Take foods rich in Vitamins so that you will be able to coat your throat with proper nutrients to help strengthen your throat,you can as well take vitamin supplements
7)maintain good oral hygiene
Avoid smoking and pollutants entering your system
9)Exercise: Some exercises have been proven to strengthen the voice, breathing exercises help to strengthen the lung and thus enable one to hold and control breath when reciting the Quran
10) Avoid hard drugs, alcohol,they all destroy the vocal cord
11)A cup of warm peppermint tea with two teaspoonfuls of liquid honey has been said to sooth the vocal cords and make the voice mellifluous

Jazaki llahu khair.�