How can I practice by myself?

Naturally, Aikido is best learned with a partner. However, there are a number of ways to pursue solo training in Aikido. First, one can practice solo forms (kata) with a jo or bokken. Second, one can "shadow" techniques by simply performing the movements of Aikido techniques with an imaginary partner. Even purely mental rehearsal of Aikido techniques can serve as an effective form of solo training.