You want to carry less weight with you. Start with your wallet. Use one which has a minimalist design. You also need to reduce the items you carry with you. Carry only one card in place of multiple cards. When going out to a short distance, a single card may be sufficient for most payment purposes. A slim bifold wallet will be sufficient for carrying most important items like a few cards and some amount of cash. This thin model can be carried in the pocket comfortably.
The slim wallet does not take much space but still has sufficient pockets and space to fit all your cash and cards. It is not too minimalist like the front pocket wallet which makes it difficult to carry more than a few items. The bifold wallet gives you more space to carry more items. This slim wallet can be carried even in the front pocket.