Does anybody happen to know how I could set up h2o with digitalocean?

here's what I would like to do:
1) run a 8gb ubuntu droplet on digitalocean
2) install h2o
3) initiate h2o instance on digitalocean droplet
4) connect to h2o instance from Rstudio on my laptop
5) run my machine learning code where the computations are done in the h2o instance on digitalocean

So far all goes well until I reach number 4 -> when I try to connect I get the following error at the h2o instance on the digitalocean droplet:

.5:54321 ERRR: Got IO error when sending batch UDP bytes: java.net.ConnectException: Connection refused

This is actually not so surprising as I would expect that I need to somehow configure the droplet to allow a secure connection from my laptop; however I have no idea how to approach this and couldn't find any documentation on it.

Does anybody know how I should proceed?
Thanks!