Voöbus, Arthur. "Part 1: On the Rite of Baptism." "Chapter One: Tradition Regarding Baptism." Liturgical Traditions in the Didache. Stockholm: ETSE, 1968, 17-27.
Voöbus notes that the Didache's chapter pertaining to baptism (chapter seven) is relatively short, and, further, it gives relatively little indication of the nature of catechesis preparatory for baptism (Voöbus 1968, 17). While there is a statement about speaking the materials from chapters 1-6, it is unclear whether that is a part of the baptismal ceremony or an outline for prior catechesis. Voöbus takes the command as an indication of catechetical instruction (Voöbus 1968, 18). This would be consistent with what we know from other sources about catechesis in Jewish proselyte baptism or Jewish Christianity. Of note to Voöbus is that the material content of the catechesis is moral in nature, not dealing with Christ and the atonement or other highly theological elements (Voöbus 1968, 19).
The purpose of a fast prior to baptism is not made clear, but the duration of one or two days is, as well as the call for as many involved in the baptism as can participate in the fast. This is more clear guidance than is found in other sources(Voöbus 1968, 20-21).
In the baptism itself, the candidate is baptized "into the name" of the Lord. Voöbus sees this as indicating a transfer into the service of the Lord (Voöbus 1968, 21). If possible, the baptism is to use "living water." Voöbus interprets this as being either water from a stream or from a well (Voöbus 1968, 22). If living water is not available, it is possible to use other water, whether cold or warm. Voöbus notes that some scholarship suggests it is warmed for children or the sick (Voöbus 1968, 23). However, he finds a prevailing pattern within Judaism to refer to water which has lost its original temperature as "warm." This would apply to water in a reservoir or a cistern (Voöbus 1968, 24). A mode of baptism, such as immersion, is not specified. However, if no adequate supply of water is present, water may be poured over the head three times (Voöbus 1968, 26).
Voöbus observes that we are not told who would perform a baptism, or whether there was a consecration of the water (Voöbus 1968, 26). We are also not told what to expect as far as the meaning of baptism. Though it is a prerequisite for communion, we are not given any additional expectations (Voöbus 1968, 27).