The striker appeared on the training pitch for the first time on Sunday, as the team had their recovery session after the 1-0 victory against Tondela at Estádio do Dragão.
Head Coach Sérgio Conceição also focused on several aspects of preparation ahead of the League Cup semi-finals clash against Sporting Lisbon.
Waris completed a loan move until the end of the season from French second division side Lorient on Friday after completing a medical.
The Dragons retain the option to make the deal permanent for €6m at the end of his loan spell.
Waris could be set for his debut in the crucial semi-final match against Sporting on Wednesday.