It is important to keep accurate records.  The family tree sheet is used one per family.  Add all pertinent data including your sources.  They can be verbal sources from those still alive, but copies of documents are a better source if you can get them, such as birth certificates, marriage licenses, etc.  It is worth the time you spend on each family as the more you trace back the more families you’ll have and it can become overwhelming. Try out this sheet by copy and paste.

Family Group Sheet: