Buying hosting takes a few minutes. The decisions worth pausing on are the term length, whether you register a domain at the same time, and which of the offered extras you actually need, because the renewal price is usually higher than the introductory one, and that is the number you will be paying long-term.
Choose the plan
Pick from the hosting pages: web hosting for a general site, WordPress hosting for a WordPress site, reseller hosting if you will host for others, VPS or dedicated if you need root access.
If you are unsure between shared and VPS, start shared. Moving up later is a migration in place of a rebuild, and buying a server you do not maintain is the expensive mistake. Comparing the tiers explains the decision.
Read the renewal price, not the headline
This is the single thing worth checking before anything else.
Hosting is sold with an introductory rate for the first term and a higher rate afterwards. Both are stated (on Ahosting's WordPress plan the page says $2.79 introductory and $9.79 on renewal) but people read the first number and plan around it.
Work out what you will pay in year two and decide whether that is acceptable. If it is, the introductory discount is a genuine saving. If it is not, you will be migrating in twelve months, which costs more than the difference.
Domain: register, transfer, or use one you have
Three options at checkout.
Register a new one. Simplest, and it arrives already pointing at the hosting.
Transfer an existing one. Moves the registration here, usually adding a year to its expiry. It takes several days and is not required. Transferring your domain sets out when it is worth doing.
Use one registered elsewhere. Perfectly fine. You point it at the hosting by changing its nameservers, and the registration stays where it is.
The third is the default answer if you already have a domain. There is no requirement to move a registration in order to host somewhere.
The term
Longer terms lock in the introductory rate for their whole duration. A three-year term pays the introductory price for three years; a one-year term pays it for one and then renews higher.
The trade is money committed upfront to a host you have not used. If you have never used them, take a shorter term and extend later. The discount is still available at renewal.
The 30-day money-back guarantee limits the downside either way, which makes this a smaller decision than it looks.
The extras
Checkout offers additions. Two are worth understanding.
SSL certificate. Ahosting includes free SSL on every plan, so a paid certificate is only worth buying if a partner or auditor specifically requires one. The encryption is identical. Free versus paid SSL explains it honestly.
Domain privacy. Hides your personal details from public WHOIS records. Worth having on a domain registered to an individual; largely irrelevant for a registered company whose address is public anyway.
Anything else, decline for now. You can add services later, and buying things you have not needed yet is how a cheap plan becomes an expensive one.
Account details
Use an email address you actually read, and not one hosted on the domain you are about to set up. Every important message goes there: account details, renewal notices, password resets, and if it is on the site you are building, a problem with the site takes the notifications with it.
Enter accurate billing details. Mismatched details are the most common reason a card is declined.
Payment and what happens next
Complete payment and the account is usually provisioned within minutes. If it is not immediate, the order may be held for a routine fraud check: more common on a first order, or when the billing address does not match the card. Completing your payment deals with what to do.
The welcome email is the important one. It contains your cPanel address, username, password and the nameservers to point your domain at. Save it somewhere you will find it again.
Then activating your hosting service goes over the first steps.
If you are moving an existing site
Do not change your domain's nameservers yet. Set the site up here first, test it, and switch only when it works: otherwise visitors see a broken site while you build.
Ahosting offers free migration, so opening a ticket and providing access to the old host is usually the better route than doing it yourself. Requesting a free migration deals with what to provide.
Read what the plan actually includes before ordering
The comparison table states the headline figures and the constraints that matter are usually elsewhere. Check what happens at each limit, whether backups are included and for how long, which versions of the underlying software are available, and what the renewal price is rather than the introductory one. Each of those changes the value of the plan more than the disk figure does. Asking before ordering gets a straight answer; asking afterwards gets an explanation of what you already bought, which is a different conversation.