There are many promotional options available to you...

You can promote continuously on cryptocurrency forums like Reddit, cryptocompare and cryptoroom.org
Target cryptopreneurs and specific crypto channels on other general forums like quora and promote
Also, by  sparing some little drops of the tokens listed on your exchange to your users, you can rapidly grow your community...

These are jus a few options... All the best

yes

Is this a digital asset exchange like hitbtc for example? You should tell us the name of your exchange if this is a reputable and no bad records from the community then this forum is one of the best platform to promote your company as there are many crypto traders here follow the advise of some members start a signature campaigns its proven. 

I think the best way would be to increase your affiliate network, maybe motivate users for higher revenue share deals.

Good luck!

Care you share the name of your trading exchange?

You don't need to go further because this forum is your best re-course. But as others have suggested, create a ANN thread here. Sort of giving the community a glimpse of what your exchange is all about so that we can see what offers you can give us. Perhaps users will try your platforms specially if fees is significant lower than other existing trading exchanges we have right now.

What's your exchange?

@kate.poisonglen stated the general ways. To add, here's how you can advertise in Bitcointalk:

1. Make an Announcement Thread about your Exchange - since your account is a newbie, it would be better if you'll upgrade to a Copper Member to be able to post images. Read more at Newbies can now pay a small fee to enable images
2. Advertise on this forum via ad space - there's an ongoing auction now, check the details at Advertise on this forum - Round 255
3. Signature and Social Media Campaigns - they have mentioned it above. I just want to add that you should hire a trusted campaign manager for this, not really necessary but recommended (check List of Campaign Managers)

• Signature - Participants will be wearing a signature representing your exchange and it will be exposed in the forum every time the participants make a post (for ex. mine, I was wearing a BQT signature below)
• Social Media - Participants will like, follow, talk about your service on Facebook, Twitter or other social networking sites

Normal thing to happen which you would really lose up users due to this kind of handling but im still amazed that you do able to sustain for 5 years which we cant see on most exchangers but still even those new do able to get to the top spot because they done the proper way of advertising at the same time giving out the best service among traders in the market. First off, marketing do really matter which you should allocate funds into this one where advertising your exchange into this forum itself will be a good start and as suggested above try to run up a signature campaign, making ANN threads, social medias and all sorts as long it would spread awareness of this exchange but be sure that your exchange would be ready to meet users demands or expectations which can tie up with famous exchangers too if you do like to succeed.

Well, i think the best option is to promote it with a signature campaign on this forum, campaigns aren't cheap at all, but they are an efficient way to promotion any cryptos related business.

Other way would be with Google and Facebook campaigns, you know those kind of campaigns where you pay each click you get, but those companies say each click is a potential client, so, sometimes worth it.

The user above covered it all in a nutshell but you should start by creating your own thread on marketplace, services, or on service discussion section here in this forum if you haven't already started a thread here. Another good first step to advertise your exchange is to start a signature campaign, reddit campaign or social media campaign if your team can afford it.

The whole crypto market doesn't feel well these days, so it's not only about exchange platforms. All crypto projects lose users.
Still, if you have a viable product and a good offer you may still save your boat from drowning. Try the following:

1. Promote your platform on Quora, Reddit and all cryptocurrency-related forums in the relevant topics.
2. Find reputable services with crypto-oriented audience and contact them for cross-promotion.
3. Contact all the coins that are supported by your platforms and ask them to place the link to your platforms in the "exchanges" section.
4. If you already have some audience on social media, run a promo campaign. E.g. "No fees for 3 days for reposting our service on Facebook and Twitter". Duplicate this promo campaign via email marketing.
5. SEO is not dead either. A blog with many keyword-focused articles may attract more audience, but it will require lots of time and efforts. Wordpress+YoastSEO may facilitate the process.