This page will guide you and offer a simple how-to, to  set up and perform atomic swaps between Beam and Ethereum, directly from your Beam wallet. Currently, this function is only available on testnet and to begin, please see the release notes for the Beam Eager Electron 5.3.10262 testnet wallet release here: https://medium.com/beam-mw/eager-electron-5-3-10262-testnet-release-notes-701d25cba6ae

In this guide we will use the Ropsten proof of work testnet of Ethereum.

Once installed and set up, the first thing you want to do is create an account on Infura and then pair your Beam wallet to an Ethereum metamask wallet, by creating an Ethereum wallet seed phrase, in the settings page of the Beam wallet.

Infura is the api service which broadcasts information from the Ethereum blockchain.
Metamask is a browser-based Ethereum wallet, where you should hold any Ethereum you want to use in an atomic swap.

You will need to register on infura.io with a valid email address, verify your account by clicking on the link in the verification email, and then collect some info to add to your Beam wallet… 

Create a project on infura.io and give it a name. In the settings page, you will be given a project ID. See below

Copy this project ID string, and paste it into your Beam wallet, settings page in the Ethereum connectivity box, see below…

Now select ‘Generate new seed phrase’ to obtain the seed phrase which you will import into your Metamask Ethereum wallet.

You can also use a previously created seed phrase from an already generated Ethereum wallet here.

Once you have generated the seed phrase, copy it and click ‘Apply Changes’ then ‘Connect to Node’

The next step is to import the Ethereum seed phrase into a Metamask wallet, and connect to the relevant network (in this case, Ropsten.) Metamask is a browser extension and can be installed on your Brave browser or any other Chrome-based browser from the Chrome web store here. 
1. Click the link at the bottom of the window ‘Import using account seed phrase’
2. Enter your seed phrase and set up a password.
3. Get some Ethereum….

before attempting to create an Etheruem <>Beam atomic swap, you should fund your Ethereum wallet. In this instance we will use the Ethereum Ropsten Faucet to get some free testnet ETH.
Use this link: https://testnet.help/en/ethfaucet/ropsten

and request some testnet Eth to be received in your metamask ropsten ethereum wallet address…

If you have followed this guide correctly, then you will see the Ethereum you obtained from the faucet, present in the Atomic Swaps page of your Beam wallet, as below.

You can now initiate “create offer” to swap some Eth for Beam or some Beam for Eth or accept a pre-existing offer, which matches an amount of fund you hold and wish to swap. it is important that you check the current AVERAGE GAS PRICE of Ethereum to ensure that your swap completes in swift time. Using a GWEI price too low may mean that your swap gets stuck in the Ethereum fee market.
For mainnet, check https://ethereumprice.org/gas/

In this instance, since we are using Ropsten testnet, gas prices can be low but in times of excessive use, the Ethereum blockchain can require gas prices upwards of 99 gwei and at some points in time, has been as high as 400 gwei, so you will understand that it is important to double check your fee rate here.

Publish your offer, and wait for someone to accept !