There are network fees paid to miners or validators, and withdrawal fees charged by exchanges. Both vary over time.
Network fees rise when a network is congested. Transacting during quieter periods can reduce the fee significantly.
Some assets can travel on multiple networks. Using a cheaper network, such as a layer 2, can dramatically cut costs.
Withdraw larger amounts less often rather than many small amounts, since some exchanges charge a flat fee per withdrawal.
Different exchanges charge different withdrawal fees. Shopping around can save money on regular transfers.
A little planning around timing, network choice and batching can keep your fees low.