Using a digital wallet, such as MetaMask, or a wallet compatible with WalletConnect members can contribute to the LAO after they have been approved (i.e., verified as an accredited investor, passed KYC/AML checks, etc., as applicable and as further outlined here).
Ether contributions will be wrapped as ERC-20 tokens (wETH) to allow for a seamless interaction with The LAO smart contracts (described further here). The ERC-20 standard streamlines how tokens are tracked and transferred between parties. Ether itself predates the ERC-20 standard, and it did not come with a built in standard of how to track and trade tokens amongst parties. The conversion from Ether to wETH addresses this concern.
The members, acting by majority vote, have the right to elect to invest capital contributions to The LAO in either Ether, Bitcoin, and/or fee or interest bearing cryptocurrencies or other digital assets.