Just locate your closest HFT club (the soon to be non Europeans can help you more than I with that!) and spend some time there with the established members, politely looking, asking and most importantly listening. Most people will be only too happy to point you in the right direction / let you try their kit.
Or you can just dive in, spend a fortune and then realise that what you have invested in does not work for you / the discipline of HFT.
Be a little patient and take some time to learn / understand, good practice for when you finally get equipped because without those traits you shall not progress far
And ASAP just participate in as many comps as possible, don't be concerned about your experience / ability, because that is where you shall really learn and develop and ultimately be able to make informed decisions about what kit / adjustments / tweeks etc you might actually benefit from.
There are no tangible shortcuts which for most of us only adds to the attraction of the HFT & FT disciplines, have fun, most of us do!.