Spiritual communion was defined by St Thomas Aquinas as “an ardent desire to receive Jesus in the Holy Sacrament and a loving embrace as though we had already received Him”. In the present context it means for most of us not receiving the Blessed Sacrament physically.  The following prayer might be useful in making a spiritual communion:

PRAYER FOR SPIRITUAL COMMUNION

At thy feet, O my Jesus, I prostrate myself and I offer thee repentance of my contrite heart, which is humbled in its nothingness and in thy holy presence. I adore thee in the sacrament of thy love. I desire to receive thee into the poor dwelling that my heart offers thee. While waiting for the happiness of sacramental Communion, I wish to possess thee in spirit. Come to me, O my Jesus, since I for my part, am coming to thee. May thy love embrace my whole being in life and in death. I believe in thee, I hope in thee, I love thee. Amen.

Pope Francis, March 19th, 2020