Manchester City will fly to Spain immediately after their clash at Newcastle.
The friendly is organised to raise funds for amyotrophic lateral sclerosis research after ex-Barca goalkeeper and coach Juan Carlos Unzue – who worked under Guardiola - was diagnosed with the disease.
Guardiola said, "We will be together for a few days, our chairman (Khaldoon Al Mubarak) will be there with us for three days.
"There is time to train and recover in a good environment and we go because Barcelona opened their doors to make a game for an important person in our lives.
"It will be perfect and we will come back here on Thursday, recover, see the draw for the Champions League and prepare for the Palace game.
"The best way to take rhythm is playing games. Training is nice but the best way is playing games and the guys who didn't play much minutes in the first two games are going to play. After in September, with games every three days, everyone is going to play."