Environmental DNA samples can be collected and analyzed in a number of ways, but they all have some goals and methods in common: lab space dedicated to low-quantity samples, use of filter tips, and careful handling to prevent cross-contamination. This page has videos that have been produced by labs to tour practitioners through eDNA sample analysis. Additionally, there are introductory resources for learning about DNA and PCR.
Background Information on DNA Analysis
An excellent introduction to DNA can be found here: https://ghr.nlm.nih.gov/primer
Information on different DNA extraction techniques (not specific to eDNA) can be found here: https://www.qiagen.com/us/resources/molecular-biology-methods/dna/
A primer for qPCR can be found here: Qiagen – Boost qPCR:
Performing the qPCR assay: https://www.youtube.com/watch?v=QQwL13Ng6Ks (source: Southern California Coastal Water Research Project)