On how to create merits, there are some points that can be found in this topic
http://www.dorjeshugden.com/forum/index.php?topic=988.15Dear DS Friend, there are SO many ways to collect merits everyday! Sometimes even without knowing it.
From offerings to your Guru(if you have 1), the holy statue, water offerings, food offerings, butterlamps or candles, sound offerings, dana offerings, incense offerings, circumambulation of temples or stupas, reciting mantras, mandala offerings, pujas, etc.
Buddha in the Sutra of the Mudra of Developing the Power of Devotion:
The minute you see a holy object you create infinite merits,
So, no question, if you actually make prostrations,
Offerings, and so forth, you create far greater merit.For example, in India, a person made one offering to a fully ordained monk. In his next rebirth, he was a powerful king in India. This result came from offering to a powerful object and the fact that karma is expandable. Just one simple offering to a monk or nun is so powerful. Offering to numberless buddhas, the Dharma, Sangha, statues, and scriptures means you receive a lot of merit. But offering to yourself as the guru/deity gains much greater merit than offering to numberless buddhas, the Dharma, Sangha, statues, and scriptures—it is far more powerful karma.
Benefits of Offering to Buddha
Offering one tiny flower to a statue or picture of Buddha receives immeasurable, limitless, merit. All the paths to happiness result from that. With just one grain of rice or one tiny flower, you can enter the path and achieve total enlightenment—the completion of all good qualities.
After achieving enlightenment, you can liberate so many sentient beings from so much suffering and samsara and bring them to enlightenment. This is the result of offering one tiny flower. Each offering has all this benefit—like putting money in the bank. One dollar equals one billion trillion dollars in interest. This is an amazing benefit. It is important to remember this every day and offer as much as possible. If you see a beautiful flower, you visualize offering it to the guru and Buddha. The result and benefit is incredible. You can offer every single flower in a garden—the merit received is mind-blowing.
This is how you use your precious human life, which is extremely rare and hard to find. Every time you see an object, use it to become closer to liberation and enlightenment. Many times each day, use your precious human rebirth to bring you closer and closer to liberation and enlightenment and thus to enlighten all sentient beings.
One more I think you will find interesting.
Multiplying Mantras to Increase the Merit 100,000 Times:CHOM DEN DE DE ZHIN SHEG PA DRA CHOM PA YANG DAG PAR DZOG PAI SANG GYE NAM PAR NANG DZE O KYI GYAL PO LA CHAG TSAL LO (3 times)
JANG CHUB SEM PA SEM PA CHEN PO KUN TU ZANG PO LA CHAG TSAL LO (3 times)
TAYATHA OM PANCHA GRIYA AVA BODHANI SOHA
OM DHURU DHURU JAYA MUKHE SOHA (7 times)
CHOM DEN DE DE ZHIN SHEG PA DRA CHOM PA YANG DAG PAR DZOG PAI SANG GYE NGO WA DANG MON LAM THAM CHE RAB TU DU PE GYAL PO LA CHAG TSEL LO