For pure Taoists and pure Buddhists and those Western Folks who want to follow the proper methods , You have 2 choices.
The Proper Taoist Method
You should go to a Taoist Temple that worship the San Guan Da Ti (三管大帝). You will join the Priests to recite 8 Important Incantations Of Taoism , "Praise/Invitation Mantra for the Three Lord Emperors of the Three Realms" (三官大帝宝诰), and other Important Taoist Mantras for paying respect to San Guan Da Ti (三管大帝). This is the proper methods for Taoists to pray for prevention of natural disasters, releasing of illnesses and eliminating of all the negative entities.
The Proper Buddhist Method
You should go to a Buddhist Temple and join the Monks to recite several Buddhist Mantras, such as "Ullambana Sutra"(佛说盂兰盆经), Kṣitigarbha Bodhisattva Pūrvapraṇidhāna Sūtra (地藏菩萨三愿经), perform the "Food Offering To Hungry Ghosts Ceremony" (慈悲甘露施食儀軌), which includes the chanting of "Gate of Sweet Nectar Dharani" (甘露水真言)and "Transform Food Dharani"(变食真言) and also "Fan Yan Kou"(放焰口) etc. If these mantras aren't chant, food that touches the mouths of Hungry Ghosts will burn into ashes.
The Chinese Folks/Lay Men Method - Interesting and without the hustles of reciting sutras
The grand food offering method - Usually applied on 15th Day of Hungry Ghost Month
Place a table right in front of Your Main Door of Your House / Company / Shop. Display all kinds of meats, canned foods , rice , packet drinks, beers and whatever You think can be a big feasts. Poke a Triangle Flag (with Dragon Image) or one incense stick on each food , representing the food is to be offered to the Wandering Ghosts. After that, place the joss papers and hell bank notes at the side and then light up 2 candles and joss sticks to pray to the "Good Brothers" (wandering ghosts).
The simple food offering method - Usually applied on 1st Day and Last Day of Hungry Ghosts Month
Go to the grass patch outside Your house or near the road junction in the evening or night time. Display the simple food offering on the ground and also place the joss papers and hell bank notes at the side and then light up 2 candles and joss sticks to pray to the "Good Brothers" (wandering ghosts).
Ask 4D Numbers and Burn Joss Papers and Hell Bank Notes
After doing the Grand or Simple Food Offering Method, You can start seeking 4D Numbers with the Shake Cup Method (Bring Along Your Shake Cup) if You want to. After the candles and joss sticks are almost complete burning, You can begin to burn the Joss Papers and Hell Bank Notes to the Wandering Spirits. After that, pack up the Food Offerings and share the food with family members, working colleagues, Business Partners or workers.