Sending ETH to L2
We've created a simple example for you that moves ETH to the L2 - see ./boba-examples/init-fund-l2/.

Update .env

First, add a .env to /boba-examples/init-fund-l2. You will need to provide your private key.
L1_NODE_WEB3_URL=https://rinkeby.infura.io/v3/INFURA_KEY
L2_NODE_WEB3_URL=https://rinkeby.boba.network
ADDRESS_MANAGER_ADDRESS=0x93A96D6A5beb1F661cf052722A1424CDDA3e9418
PRIVATE_KEY=

Move ETH from L1 to L2

Next, adjust the amount that you want to deposit from L1 to L2 in ./boba-examples/init-fund-l2/src/index.js:
const TRANSFER_AMOUNT = ethers.utils.parseEther('0.0001')
Finally, run:
yarn install
yarn start