Reagents:
1. LB
2. Agar
3. 10 cm plastic Petri dishes (e.g. Falcon)
4. Antibiotic stock (most commonly ampicillin or kanamycin)* 100 mg/mL ampicillin (1000x, in water, store at --20C)
- 50 mg/mL kanamycin (1000x, in water, store at --20C)
Make LB media, and add agar at 1.5% (w/v). Autoclave, and allow to cool until comfortable to hold with bare hands (~50C, very important since ampicillin degrades at higher temperatures).
Add antibiotic to the proper concentration, and pour plates using proper sterile technique. Store plates at 4C.