Bacillus spores are abundant in soil. Take about a gram of soil and suspend it in several milliliters of water by vortexing it thoroughly. Heat shock the suspension by incubating a tube containing it at 80°C for 20 min. After removing the tube from the water bath, allow the soil particles to settle at room temperature for another 20 min. Remove a small sample of the upper, liquid part of the suspension and plate serial dilutions on Nutrient agar, TSA, or LB agar. Incubate overnight, preferably at about 30°C. All colonies should result from spore formers related to the genus Bacillus. The species can be identified by morphological and physiolgical tests, or more accurately by determining a partial 16S rRNA gene sequence.
You Can take some amount of soil and suspend into about 10 ml of distilled water or 5 M sodium Acetate. Then incubate it at 65 C for at least 10 min. to check spore forming the bacteria. spin it , take supernatant, dilute it at maximum and spread at LA + Penicillin plate then incubate the plates at 28 C for O/N or more. You will get mixture of colonies. Based on morphology you can select white colony which is serrated at margin. If you want BT then try 16s-23s ITS rRNA gene sequences which will give approx. 234 bp band.