Here is a simple but effective Kata for blessing your Amulets with before putting it on in the morning and leaving the house.
First of course, as in all Katas, you must chant "Na Mo Dtassa Pakawadto Arahadto Sammaa Samputtassa" first (3 times).
นะ มะ พะ ทะ นโพุทธายะ จะภะกะสะ มะอะอุ
Na Ma Pa Ta, Sang Wi taa Bu Ga Ya Ba
Na Moe Put Taa Ya, Ja Pa Ga Sa, Ma A U
At best though, you should light incense and candle on your Poojah table with your Buddha image, and place the amulet/s on the table under Buddha, bow on the floor 3 times to the triple gem and say in your heart "Puttang Saranang Kyajchaami, TammangSaranang Kyajchaami, SangkangSaranang Kyajchaami, Tudtiyambi Puttang Saranang Kyajchaami, TammangSaranang Kyajchaami, SangkangSaranang Kyajchaami, Dtadtiyambi Puttang Saranang Kyajchaami, TammangSaranang Kyajchaami, SangkangSaranang Kyajchaami"
Then you can take the amulets in your hands in praying style, and chant;
Na Mo Dtassa Pakawadto Arahadto Sammaa Samputtassa
Na Mo Dtassa Pakawadto Arahadto Sammaa Samputtassa
Na Mo Dtassa Pakawadto Arahadto Sammaa Samputtassa
Then you erect your mind and focus in front of you into the amulets with your eyes closed imagine your mind's eye being between your eyebrows and emitting a stream of thought energy - try to be aware of your total faith in the Buddha and his Dhamma and the refuge of the Sangha and really mean it in your heart. Then chant the Amulet Kata with all the faith and concentration you can muster up;
Na Ma Pa Ta, Sang Wi taa Bu Ga Ya Ba
Na Moe Put Taa Ya, Ja Pa Ga Sa, Ma A U
Then open your eyes and blow into the amulets and put them on (first put the amulets to your forehead between the eyes before putting them on).
Some amulets of course have their own special Kata, such as Luang Por Tuad Amulets (Click on link to see the Kata for this amulet and reverence of Luang Por Tuad).