How to create a travel history

If you really were refused under 214(b), it means that you failed to convince the officer of your intent to return to Germany; and it doesn't have much to do with your travel history.

As you are student, you have limited ties to Germany (there is nothing of substance preventing you from becoming a de-facto immigrant to the US) and you are a high risk applicant.

While conducting visa interviews, consular officers look at each application individually and consider the applicant's circumstances, travel plans, financial resources, and ties outside of the United States that will ensure the applicant’s departure after a temporary visit.

In your shoes, I would consider applying from India where you can demonstrate family ties.

If you want to build travel history with a reduced risk due to potential visa rejections, consider less developed countries. Many such countries do have online visa application processes, such as Myanmar and Cambodia (both are nice places to visit, too). These processes are often inexpensive (under 50 EUR), fast (less than one week), and can be done in parallel (because you need not submit your passport initially).

Between online visa applications and visas on arrival (also possible for you in e.g. Cambodia as well as other countries like Indonesia which does it for free now), it should be practical to build an itinerary in South East Asia using your Indian passport. Several of these countries also insert big pretty visa stickers in your passport, or at least stamps.

Also note that your passport comes from a member nation of the South Asian Association for Regional Cooperation. The list of nations there may be useful as well, because you are afforded some amount of special status in many or all of them.

Only way to build the travel history is by of course travelling like Micheal told you.

Micheal has answered this extensively , However I wanted to give you my tips to do this as I have done the same thing in last 7 years.

Travel History is NOT everything to get a US Visa, Sometimes TOO MUCH travel may actually make Consular believe that you do not have enough ties to home.

Like you I believed it is Huge reason so here is how I accomplished it if you want to build some confidence.

I was rejected for B1 visa to USA on 2009, 2010 and 2012 all due to 214B lack of ties to home.

Looking to build travel history I applied for Schengen visa to Belgium on 2011 & France on 2013 and both rejected me as well and every visa denial was all related to the ties to home. This was a huge mistake to apply immediately to another Western country after a rejection. I learnt it tad late

So I started travelling to the obvious destinations for Indians first like Singapore/Malaysia/Thailand then I went for slightly harder ones like HK, China, Phillipines,etc Then I completed almost ALL of SE Asia without spending huge money as AirAsia/Tiger helps you with that.

Then I went for Japan. They have one of the decent visa programme 500 INR for visa which is refunded on the refusal and its straight forward.

After I got the Single entry Japan visa which allowed me to also go to Taiwan on ETA , I traveled to both Japan/Taiwan.

Then I applied tourist visa for Australia and I visted there , then I applied for both UK/Canada at the same time and I got those visas as well.

I applied for Schengen now again that I have quite a few visas, got approved and I visited France/Belgium/UK.

Then finally I went for the USA Visa and I got that approved as well.

Now to answer your question I would ask you to go with HK visa free then / Japan then to UK OR Australia then with some travel in your passport go for USA visa.

During all this visa experiences of mine and friends , I came to know that Travel history is not that big of a deal compared to other ties to home when it comes to USA.

They even reject people that have visited Canada/UK/etc before.

most USA consular don't even look at your old passports or any documentations so things that help are the things you can mention on the DS-160 which prove your ties like you are married/have kids / have a business/ have a decent pay/etc .

Travel history DOES help you with acquiring visas for most other countries just not as much for USA Visa compared to others..

However along with the travel history I would advise you to prove/build your ties to Home and Enjoy travelling as a whole and not just for the travel history.